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TABLE OF CONTENTS

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The information in this preliminary prospectus supplement is not complete and may be changed. This preliminary prospectus supplement and the accompanying prospectus are not an offer to sell these securities and are not soliciting an offer to buy these securities in any state where the offer or sale is not permitted.

Subject to Completion
Preliminary Prospectus Supplement dated October 14, 2014

Filed Pursuant to Rule 424(b)(5)
Registration No. 333-194661

PROSPECTUS SUPPLEMENT
(To Prospectus dated March 18, 2014)

6,500,000 Shares

LOGO

Common Shares of Beneficial Interest


We are offering 6,500,000 of our common shares of beneficial interest, par value $0.01 per share, or common shares.

Our common shares are listed on the New York Stock Exchange (the "NYSE") under the symbol "CUBE." The last reported sale price of our common shares on the NYSE on October 13, 2014 was $19.03 per share.

Our common shares are subject to certain restrictions on ownership and transfer designed to preserve our qualification as a real estate investment trust for federal income tax purposes, among other purposes. See "Description of CubeSmart's Capital Shares — Restrictions on Ownership and Transfer" in the accompanying prospectus.


Investing in our common shares involves a high degree of risk. See "Forward-Looking Statements" beginning on page S-iii of this prospectus supplement, "Risk Factors" beginning on page S-4 of this prospectus supplement and "Risk Factors" set forth in our most recent Annual Report on Form 10-K for the year ended December 31, 2013 and subsequently filed periodic reports which are incorporated by reference in this prospectus supplement and in the accompanying prospectus.


 
  Per Share   Total  

Initial price to public

  $     $    

Underwriting discounts and commissions

  $     $    

Proceeds, before expenses, to CubeSmart

  $     $    

The underwriters may also exercise their option to purchase up to an additional 975,000 shares from us at the public offering price less the underwriting discount and commissions, for 30 days after the date of this prospectus supplement.

Neither the Securities and Exchange Commission nor any state securities commission has approved or disapproved of these securities or passed on the adequacy or accuracy of this prospectus supplement or the accompanying prospectus. Any representation to the contrary is a criminal offense.

The shares will be ready for delivery on or about                      , 2014.


Barclays   Jefferies

   

The date of this prospectus supplement is October                             , 2014.


Table of Contents


TABLE OF CONTENTS

PROSPECTUS SUPPLEMENT

About this Prospectus

 
S-ii

Forward-Looking Statements

  S-iii

Summary

  S-1

Risk Factors

  S-4

Use of Proceeds

  S-6

Underwriting

  S-7

Legal Matters

  S-14

Experts

  S-14

Incorporation of Certain Information by Reference

  S-14

Where You Can Find More Information

  S-16


PROSPECTUS

About this Prospectus

 
1

Where You Can Find More Information

  1

Incorporation of Certain Information by Reference

  1

Forward-Looking Statements

  3

CubeSmart And The Operating Partnership

  5

Risk Factors

  6

Use of Proceeds

  6

Ratio of Earnings to Fixed Charges and Ratio of Earnings to Combined Fixed Charges and Preference Dividends

  7

Description of CubeSmart's Capital Shares

  8

Description of Depositary Shares

  17

Description of Subscription Rights

  20

Description of Warrants

  21

Description of The Debt Securities

  23

Material Federal Income Tax Considerations

  38

Plan of Distribution

  71

Legal Matters

  73

Experts

  73

          You should rely only on the information contained or incorporated by reference in this prospectus supplement, the accompanying prospectus or any applicable free writing prospectus filed with the Securities and Exchange Commission (the "SEC") in connection with this offering. We have not, and the underwriters have not, authorized anyone to provide you with additional or different information. If any person provides you with additional or different information, you should not rely on it. Neither we nor the underwriters are making an offer to sell common shares in any jurisdiction where the offer or sale is not permitted. You should assume that the information appearing in this prospectus supplement, the accompanying prospectus, any such free writing prospectus and the documents incorporated by reference herein and therein is accurate only as of their respective dates. Our business, financial condition, results of operations and prospects may have changed since those dates.

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ABOUT THIS PROSPECTUS SUPPLEMENT

          This document is in two parts. The first part is this prospectus supplement, which describes the specific terms of this offering and also adds to, or updates, information contained in the accompanying prospectus and the documents incorporated by reference into this prospectus supplement and the accompanying prospectus. The second part, the accompanying prospectus dated March 18, 2014, gives more general information about our common shares and other securities we may offer from time to time, some of which may not apply to this offering.

          You should carefully read this prospectus supplement, the accompanying prospectus and the additional information incorporated by reference herein before investing in our common shares. See "Incorporation of Certain Information By Reference" and "Where You Can Find More Information" in this prospectus supplement and in the accompanying prospectus. These documents contain important information that you should consider before making your investment decision. This prospectus supplement and the accompanying prospectus contain the terms of this offering of common shares. This prospectus supplement may add, update or change information contained in or incorporated by reference in the accompanying prospectus. To the extent that there is a conflict between the information contained in this prospectus supplement, on the one hand, and the information contained in the accompanying prospectus or in a filing we make with the SEC under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), prior to the date hereof, on the other hand, the information in this prospectus supplement shall control. In addition, any statement in a filing we make with the SEC after the date of this prospectus supplement that adds to, updates or changes information contained in this prospectus supplement, the accompanying prospectus or an earlier filing we made with the SEC shall be deemed to modify and supersede such information in this prospectus supplement, the accompanying prospectus or the earlier filing.

          As used in this prospectus supplement, unless the context otherwise requires, references to "CubeSmart" refer to CubeSmart, a Maryland real estate investment trust, or "REIT;" references to the "Operating Partnership" refer to CubeSmart, L.P., a Delaware limited partnership; and references to "we," "us," "our" or similar expressions refer collectively to CubeSmart and its consolidated subsidiaries (including the Operating Partnership).

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FORWARD-LOOKING STATEMENTS

          This prospectus supplement and the accompanying prospectus, together with other statements and information publicly disseminated by CubeSmart and the Operating Partnership, contain certain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933, as amended (the "Securities Act") and Section 21E of the Exchange Act. Forward-looking statements include statements concerning our plans, objectives, goals, strategies, future events, future revenues or performance, capital expenditures, financing needs, plans or intentions relating to acquisitions and other information that is not historical information. In some cases, forward-looking statements can be identified by terminology such as "believes," "expects," "estimates," "may," "will," "should," "anticipates," or "intends" or the negative of such terms or other comparable terminology, or by discussions of strategy. Such statements are based on assumptions and expectations that may not be realized and are inherently subject to risks, uncertainties and other factors, many of which cannot be predicted with accuracy and some of which might not even be anticipated. Although we believe the expectations reflected in these forward-looking statements are based on reasonable assumptions, future events and actual results, performance, transactions or achievements, financial and otherwise, may differ materially from the results, performance, transactions or achievements expressed or implied by the forward-looking statements. As a result, you should not rely on or construe any forward-looking statements in this prospectus supplement or the accompanying prospectus, or which management may make orally or in writing from time to time, as predictions of future events or as guarantees of future performance. We caution you not to place undue reliance on forward-looking statements, which speak only as of the date of this prospectus supplement or as of the dates otherwise indicated in the statements. All of our forward-looking statements, including those in this prospectus supplement or the accompanying prospectus, are qualified in their entirety by this statement.

          There are a number of risks and uncertainties that could cause our actual results to differ materially from the forward-looking statements contained in, contemplated by or incorporated by reference in this prospectus supplement or the accompanying prospectus. Any forward-looking statements should be considered in light of the risks and uncertainties referred to in this prospectus supplement, the accompanying prospectus, our most recent Annual Report on Form 10-K and subsequently filed reports with the SEC, which are incorporated by reference in this prospectus supplement and in the accompanying prospectus. These risks include, but are not limited to, the following:

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          Given these uncertainties and risks, prospective investors are cautioned not to place undue reliance on these forward-looking statements. Except with respect to such material changes to our risk factors as may be reflected from time to time in our quarterly filings or as otherwise required by law, we are under no obligation to, and expressly disclaim any obligation to, update or revise any forward-looking statements included or incorporated by reference in this prospectus supplement or the accompanying prospectus, whether as a result of new information, future events or otherwise. Because of the factors referred to above, the future events discussed in or incorporated by reference in this prospectus supplement or the accompanying prospectus may not occur and actual results, performance or achievement could differ materially from that anticipated or implied in the forward-looking statements.

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SUMMARY

          The information below is only a summary of more detailed information included elsewhere or incorporated by reference in this prospectus supplement and the accompanying prospectus. This summary does not contain all the information that is important to you or that you should consider before you invest in our common shares. The other information is important, so please read carefully this prospectus supplement and the accompanying prospectus, as well as the information incorporated by reference, before you invest in our common shares.


Overview

          CubeSmart is a self-administered and self-managed real estate investment trust, or "REIT," focused primarily on the ownership, operation, management, acquisition and development of self-storage facilities in the United States.

Facilities

          As of June 30, 2014, we owned 387 self-storage facilities located in 21 states and in the District of Columbia containing an aggregate of approximately 26.1 million rentable square feet. In addition, as of June 30, 2014, we managed 159 facilities for third parties, bringing the total number of facilities we owned and/or managed at June 30, 2014 to 546.

          As of June 30, 2014 we owned facilities in the District of Columbia and the following 21 states: Arizona, California, Colorado, Connecticut, Florida, Georgia, Illinois, Indiana, Maryland, Massachusetts, Nevada, New Jersey, New Mexico, New York, North Carolina, Ohio, Pennsylvania, Tennessee, Texas, Utah and Virginia. In addition, as of June 30, 2014, we managed facilities for third parties in the following 23 states: Alabama, Arizona, California, Colorado, Florida, Georgia, Illinois, Louisiana, Maryland, Massachusetts, Michigan, Minnesota, Mississippi, New Hampshire, New Jersey, New York, North Carolina, Pennsylvania, Rhode Island, South Carolina, Tennessee, Texas, and Virginia.

          Our self-storage facilities are located in major metropolitan and rural areas and we have numerous tenants per facility. No single tenant represents a significant concentration of revenues.

Recent Developments

          As previously disclosed in our Current Report on Form 8-K, filed on August 25, 2014, the Operating Partnership entered into an Agreement for Purchase and Sale with certain limited liability companies controlled by HSRE REIT I and HSRE REIT II, each Maryland real estate investment trusts (collectively, the "Sellers"), to acquire (the "HSRE Acquisition") 26 self-storage facilities for an aggregate purchase price of $223.0 million plus customary closing costs. The HSRE Acquisition will close in two tranches. We have completed our due diligence on all of the facilities and expect to close the first tranche of 22 facilities no later than November 3, 2014. We expect to close on the remaining four facilities no later than March 31, 2015. In addition to the HSRE Acquisition, the Operating Partnership has entered into agreements for purchase and sale to acquire eight facilities (collectively with the HSRE Acquisition, the "Acquisitions") for an aggregate purchase price of $146.0 million plus customary closing costs, which are scheduled to occur no later than December 31, 2015.

          The material terms of the purchase agreements for the Acquisitions contain customary representations, warranties and covenants of the contracting parties. The Operating Partnership is entitled to inspect the facilities with respect to environmental, physical condition, title and survey matters. Subject to certain conditions and limitations, the Operating Partnership may disapprove the facilities and terminate any of the purchase agreements based on such due diligence results, in which event the deposit for such acquisition will be returned to the Operating Partnership. As a result, there can be no assurance that the Acquisitions will close on the terms described above or at all. The aggregate value of the deposits made by the Operating Partnership in connection with the Acquisitions is $14.3 million.

 

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          Subsequent to June 30, 2014, the Operating Partnership acquired four facilities for an aggregate purchase price of $46.6 million.

          Since June 30, 2014, we have sold 8,018,247 common shares pursuant to our at-the-market offering program at an average price of $18.62 per share, raising net proceeds, after sales commissions, fees and expenses, of approximately $147.1 million. We used the net proceeds from these sales for general business purposes, including facility acquisitions, capital expenditures, repayment of borrowings under our revolving credit facility and other corporate purposes.

Corporate

          We were formed in July 2004 as a Maryland REIT. We own our assets and conduct our business through the Operating Partnership and its subsidiaries. We control the Operating Partnership as its sole general partner and, as of June 30, 2014, we owned an approximately 98.5% interest in the Operating Partnership. The Operating Partnership has been engaged in virtually all aspects of the self-storage business, including the development, acquisition, management, ownership and operation of self-storage facilities.

          Our executive offices are located at 5 Old Lancaster Road, Malvern, Pennsylvania 19355 and our telephone number is (610) 535-5700.

 

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THE OFFERING

Issuer   CubeSmart.

Common shares offered by us

 

6,500,000 shares. The underwriters may also exercise their option to purchase up to an additional 975,000 shares from us at the price set forth on the front cover of this prospectus supplement for 30 days after the date of this prospectus supplement.

Common shares outstanding immediately after the offering

 

161,082,459 shares (162,057,459 shares if the underwriters exercise their option to purchase additional shares in full).

Use of Proceeds

 

We intend to contribute the net proceeds from this offering to the Operating Partnership in exchange for partnership units of the Operating Partnership having identical economic terms. The Operating Partnership intends to use the net proceeds from this offering for general business purposes, including, without limitation, facility acquisitions, including the funding of the Acquisitions if they close, developments, joint ventures, capital expenditures, working capital and other general corporate purposes. See "Use of Proceeds" in this prospectus supplement.

Restrictions on Ownership and Transfer

 

Our charter imposes restrictions on ownership and transfer of our common shares to assist us in complying with certain federal income tax requirements applicable to real estate investment trusts, among other purposes. See "CubeSmart's Capital Shares — Restrictions on Ownership and Transfer" in the accompanying prospectus.

NYSE Symbol

 

"CUBE"

Risk Factors

 

Investing in our common shares involves a high degree of risk. See "Forward-Looking Statements" beginning on page S-iii of this prospectus supplement, "Risk Factors" beginning on page S-4 of this prospectus supplement and "Risk Factors" set forth in our most recent Annual Report on Form 10-K for the year ended December 31, 2013 and subsequently filed periodic reports which are incorporated by reference in this prospectus supplement and in the accompanying prospectus.

          For additional information concerning our common shares, see "Description of CubeSmart's Capital Shares" in the accompanying prospectus. For a description of the U.S. federal income tax considerations relating to the purchase, ownership and disposition of our common shares, see "Material Federal Income Tax Considerations" in the accompanying prospectus.

 

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RISK FACTORS

          An investment in our common shares involves a high degree of risk. In consultation with your own financial and legal advisers, you should consider carefully, among other matters, the factors set forth below as well as the risk factors set forth in our most recent Annual Report on Form 10-K and any subsequently filed periodic reports that are incorporated by reference in this prospectus supplement and in the accompanying prospectus before deciding whether an investment in our common shares is suitable for you. Additional risks not presently known to us or that we currently deem immaterial may also adversely affect our business operations. These risks could materially adversely affect, among other things, our business, financial condition or results of operations, and could cause the trading price of our common shares to decline, resulting in the loss of all or part of your investment.

Risks Related to the Offering

A large number of our common shares available for future sale could adversely affect the market price of our common shares and may be dilutive to current shareholders.

          The sales of a substantial number of our common shares, or the perception that such sales could occur, could adversely affect the price for our common shares. Our Board of Trustees may authorize the issuance of additional authorized but unissued common shares or other authorized but unissued securities at any time, including pursuant to equity incentive plans. In addition, we have filed a registration statement with the SEC, allowing us to offer, from time to time and at any time, an indefinite amount of equity securities (including common or preferred shares), subject to market conditions and other factors. Accordingly, we may, from time to time and at any time, seek to offer and sell our equity securities, including sales of our common shares in this offering, based upon market conditions and other factors.

This offering may have a dilutive effect on our earnings per share and funds from operations per share.

          This offering may have a dilutive effect on our earnings per share and funds from operations per share after giving effect to the issuance of our common shares in this offering and the receipt of the expected net proceeds. The actual amount of dilution from this offering, or from any future offering of our equity securities, cannot be determined at this time. The market price of our common shares could decline as a result of sales of a large number of our common shares in the market pursuant to this offering, or otherwise, or as a result of the perception or expectation that such sales could occur.

Future offerings of debt or equity securities may adversely affect the market price of our common shares.

          In the future, we may attempt to increase our capital resources by making offerings of debt or additional offerings of equity securities, including commercial paper, medium-term notes, senior or subordinated notes, and classes of preferred shares. If we decide to issue senior securities in the future, it is likely that they will be governed by an indenture or other instrument containing covenants restricting our operating flexibility. Holders of senior securities may be granted specific rights, including the right to hold a perfected security interest in certain of our assets, the right to accelerate payments due under an indenture, rights to restrict dividend payments, and rights to require approval to sell assets. Additionally, any convertible or exchangeable securities that we issue in the future may have rights, preferences, and privileges more favorable than those of our common shares and may result in dilution of owners of our common shares. We and, indirectly, our shareholders, will bear the cost of issuing and servicing such securities. Upon liquidation, holders of our debt securities and preferred shares, and lenders with respect to other borrowings, will receive a distribution of our available assets prior to the holders of our common shares. Additional equity offerings may dilute the holdings of our existing shareholders or reduce the market price of our common shares, or both. Our preferred shares, if issued, could have a preference on liquidating distributions or a preference on dividend payments that could limit our ability to make a dividend distribution to the holders of our common shares. Because our decision to issue securities in any future offering will depend on market conditions and other factors beyond our control, we cannot predict or estimate the amount, timing, or nature of our future offerings.

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Thus, holders of our common shares bear the risk of our future offerings reducing the market price of our common shares and diluting their shareholdings in us.

Risks Related to the Acquisitions

We may not complete the Acquisitions and our shareholders may not realize any benefits from the proposed transactions.

          The purchase agreements for the Acquisitions contain closing conditions that need to be satisfied before the Acquisitions can be consummated. The satisfaction of many of these conditions is outside of our control, and we therefore cannot assure you that any of the Acquisitions will be consummated. These conditions include, among other things, satisfactory examination of the title to the facilities, the ability to obtain title insurance and customary closing conditions.

          Moreover, in the event we are unable to complete the Acquisitions, we will have incurred significant legal, accounting and other transaction costs in connection with the Acquisitions without realizing the expected benefits. In addition, if we breach any of our representations or warranties set forth in the purchase agreement for the HSRE Acquisition through intentional acts or omissions in violation of the terms thereof, we may be required to pay certain amounts held in escrow as liquidated damages.

Depending on the exact combination of financing sources we use to fund the Acquisitions, our key financial indicators may be negatively affected.

          We expect to fund the Acquisitions through a combination of cash on hand and advances under the Operating Partnership's undrawn portion of our $300.0 million unsecured credit facility. We cannot assure you of which combination of funding sources we ultimately may use. Depending on the financing arrangements, our indebtedness may increase substantially and our interest and fixed charge coverage ratios and other key financial indicators may be negatively affected.

We may not be able to successfully integrate the facilities to be acquired as part of the Acquisitions into our operations, which would adversely affect our results of operations and financial conditions.

          The success of the Acquisitions will depend, in part, on our ability to:

          If we are unable to successfully integrate these facilities into our operations, our results of operations and financial condition may be adversely affected.

We may be responsible for unknown material liabilities associated with the HSRE Acquisition which would adversely affect our business and for which we have limited recourse against the Sellers.

          We may be exposed to liabilities relating to the facilities comprising the HSRE Acquisition that we failed to discover prior to September 29, 2014 or that may arise after the HSRE Acquisition is completed. These liabilities may include liabilities that arise from litigation or non-compliance with environmental laws by prior owners for which we, as a successor owner, may be responsible. In the event that the Sellers breach any of their representations or warranties, our sole and exclusive remedy would be to pursue a claim against the Sellers for actual damages which may not exceed $500,000, subject to a minimum of $50,000 and other limitations. Such limited recourse may not be sufficient or available to cover our liabilities in which case our results of operations may be adversely affected.

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USE OF PROCEEDS

          We estimate that the net proceeds to us from this offering will be approximately $          million after deducting underwriting commissions and discounts and other estimated offering expenses payable by us and assuming no exercise of the option granted to the underwriters to purchase up to 975,000 additional shares, and approximately $          million assuming full exercise of the option. Any additional proceeds to us resulting from an increase in the number of shares offered pursuant to this prospectus supplement will be used as described below.

          We intend to contribute the net proceeds from this offering to the Operating Partnership in exchange for partnership units of the Operating Partnership. The Operating Partnership intends to use the net proceeds from this offering for general business purposes, including, without limitation, facility acquisitions, including the funding of the Acquisitions if they close, developments, joint ventures, capital expenditures, working capital and other general corporate purposes. We own our assets and conduct our operations through the Operating Partnership and its subsidiaries. We control the Operating Partnership as its sole general partner and, as of June 30, 2014, owned an approximate 98.5% interest in the Operating Partnership.

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UNDERWRITING

          Subject to the terms and conditions set forth in an underwriting agreement, we have agreed to sell to the underwriters named below, and the underwriters have severally agreed to purchase from us, the respective numbers of common shares appearing opposite their names below:

Underwriter
  Number of Shares  

Barclays Capital Inc. 

    3,250,000  

Jefferies LLC

    3,250,000  

Total

    6,500,000  
       
       

          The underwriting agreement provides that the underwriters are obligated to purchase all the common shares in the offering if any are purchased, other than those shares covered by the option to purchase additional shares described below.

          We have agreed to indemnify the underwriters against certain liabilities, including liabilities under the Securities Act, or to contribute to payments the underwriters may be required to make in respect of those liabilities.

          The underwriters are offering the shares, subject to prior sale, when, as and if issued to and accepted by them, subject to approval of legal matters by their counsel, including the validity of the shares, and other conditions contained in the underwriting agreement, such as the receipt by the underwriters of officer's certificates and legal opinions. The underwriters reserve the right to withdraw, cancel or modify offers to the public and to reject orders in whole or in part. Sales of shares made outside of the United States may be made by affiliates of the underwriters.

Commissions and Discounts

          The underwriters propose to initially offer the shares to the public at the public offering price set forth on the cover of this prospectus and to certain dealers at that price less a concession not in excess of $         per share. After the initial offering, the public offering price, concession or any other term of the offering may be changed by the underwriters in their sole discretion.

          The following table shows the initially proposed public offering price, underwriting discount and proceeds before expenses to us. The information assumes no exercise or full exercise by the underwriters of its option to purchase up to 975,000 additional shares.

 
  Per Share   Without
Option
  With
Option
 

Initial price to public

  $     $     $    

Underwriting discounts and commissions

  $     $     $    

Proceeds, before expenses, to CubeSmart

  $     $     $    

          The expenses of the offering, not including the underwriting discount and commissions, are estimated at $150,000 and are payable by us.

Option to Purchase Additional Shares

          We have granted an option to the underwriters, exercisable for 30 days after the date of this prospectus supplement, subject to the conditions contained in the underwriting agreement, to purchase up to 975,000 additional shares at the public offering price less the underwriting discounts and commissions.

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Lock-Up Agreements

          We and each of our trustees and executive officers have agreed, subject to certain exceptions described below, that, without the prior written consent of the underwriters, we and they will not, subject to certain exception, during the period beginning on and including the date of this prospectus supplement through and including the date that is the 45th day after the date of this prospectus supplement, directly or indirectly:

whether any transaction described in the first or third bullet point above is to be settled by delivery of our common shares, other capital shares, other securities, in cash or otherwise, or publicly announce an intention to do any of the foregoing. Moreover, if:

the restrictions described in the immediately preceding sentence will continue to apply until the expiration of the 18-day period beginning on the date of issuance of the earnings release or the occurrence of the material news or material event, as the case may be, unless the underwriters waive, in writing, that extension.

          Notwithstanding the provisions set forth in the immediately preceding paragraph, we may, without the prior written consent of the underwriters:

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          The restrictions of the lock-up agreements which our trustees and executive officers are party to do not apply to the following:

provided that (1) for all transfers described in the first two bullets above, the recipient enters into a lock-up agreement in a form satisfactory to the underwriters no later than one business day before the transfer, (2) for transfers (a) by will, intestate succession or pursuant to certain trusts, any report required to be filed under specified sections of the Exchange Act will state the reason for the transfer and that the transfer was not for value, and (b) for all transfers described in the second bullet above, no report under specified sections of the Exchange Act is required to be filed during the period the above restrictions apply (as the same may be extended), and (3) for all transfers described in the first two bullets above, no other filing with the SEC or any other public report, filing or announcement is made in connection with the transfer.

          The underwriters may, in their sole discretion and at any time or from time to time, without notice, release all or any portion of the shares or other securities subject to the lock-up agreements. Any determination to release any shares or other securities subject to the lock-up agreements would be based on a number of factors at the time of determination, which may include the market price of the common shares, the liquidity of the trading market for the common shares, general market conditions, the number of shares or other securities proposed to be sold or otherwise transferred and the timing, purpose and terms of the proposed sale or other transfer.

New York Stock Exchange Listing

          The shares are listed on the NYSE under the symbol "CUBE."

Short Positions

          In connection with the offering, the underwriters may purchase and sell our common shares in the open market. These transactions may include short sales, purchases on the open market to cover positions created by short sales and stabilizing transactions. Short sales involve the sale by the underwriters of a greater number of shares than they are required to purchase in the offering. "Covered" short sales are sales made in an amount not greater than the underwriters' option to purchase additional shares described above. The underwriters may close out any covered short position by either exercising their option to purchase additional shares or purchasing shares in the open market. In determining the source of shares to close out the covered short position, the underwriters will consider, among other things, the price of shares available for purchase in the open market as compared to the price at which they may purchase shares through the option granted to them. "Naked" short sales are sales in excess of such option. The underwriters must close out any naked short position by purchasing shares in the open market.

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A naked short position is more likely to be created if the underwriters are concerned that there may be downward pressure on the price of our common shares in the open market after pricing that could adversely affect investors who purchase in the offering.

          Similar to other purchase transactions, the underwriters' purchases to cover the syndicate short sales may have the effect of raising or maintaining the market price of our common shares or preventing or retarding a decline in the market price of our common shares. As a result, the price of our common shares may be higher than the price that might otherwise exist in the open market. The underwriters may conduct these transactions on the NYSE, in the over-the-counter market or otherwise.

          Neither we nor the underwriters make any representation or prediction as to the direction or magnitude of any effect that the transactions described above may have on the price of our common shares. In addition, neither we nor the underwriters make any representation that the representatives will engage in these transactions or that these transactions, once commenced, will not be discontinued without notice.

Electronic Distribution

          In connection with the offering, the underwriters or certain securities dealers may distribute the prospectus supplement and accompanying prospectus by electronic means, such as e-mail.

Other Relationships

          The underwriters and their affiliates have engaged in, and may in the future engage in, investment banking and other commercial dealings in the ordinary course of business with us or our affiliates. They have received, or may in the future receive, customary fees and commissions for these transactions.

          Jefferies LLC acts as a placement agent on our at-the-market offering program.

          In addition, in the ordinary course of their business activities, the underwriters and their affiliates may make or hold a broad array of investments and actively trade debt and equity securities (or related derivative securities) and financial instruments (including bank loans) for their own account and for the accounts of their customers. Such investments and securities activities may involve securities and/or instruments of ours or our affiliates. The underwriters and their affiliates may also make investment recommendations and/or publish or express independent research views in respect of such securities or financial instruments and may hold, or recommend to clients that they acquire, long and/or short positions in such securities and instruments.

          Other than in the United States, no action has been taken by us or the underwriters that would permit a public offering of the securities offered by this prospectus supplement and the accompanying prospectus in any jurisdiction where action for that purpose is required. The securities offered by this prospectus supplement and the accompanying prospectus may not be offered or sold, directly or indirectly, nor may this prospectus supplement and the accompanying prospectus or any other offering material or advertisements in connection with the offer and sale of any such securities be distributed or published in any jurisdiction, except under circumstances that will result in compliance with the applicable rules and regulations of that jurisdiction. Persons into whose possession this prospectus supplement and the accompanying prospectus comes are advised to inform themselves about and to observe any restrictions relating to the offering and the distribution of this prospectus supplement and the accompanying prospectus. This prospectus supplement and the accompanying prospectus does not constitute an offer to sell or a solicitation of an offer to buy any securities offered by this prospectus supplement and the accompanying prospectus in any jurisdiction in which such an offer or a solicitation is unlawful.

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Notice to Prospective Investors in Australia

          No placement document, prospectus, product disclosure statement or other disclosure document has been lodged with the Australian Securities and Investments Commission ("ASIC"), in relation to the offering. This prospectus supplement and accompanying prospectus does not constitute a prospectus, product disclosure statement or other disclosure document under the Corporations Act 2001 (the "Corporations Act"), and does not purport to include the information required for a prospectus, product disclosure statement or other disclosure document under the Corporations Act.

          Any offer in Australia of the shares may only be made to persons (the "Exempt Investors") who are "sophisticated investors" (within the meaning of section 708(8) of the Corporations Act), "professional investors" (within the meaning of section 708(11) of the Corporations Act) or otherwise pursuant to one or more exemptions contained in section 708 of the Corporations Act so that it is lawful to offer the common shares without disclosure to investors under Chapter 6D of the Corporations Act.

          The common shares applied for by Exempt Investors in Australia must not be offered for sale in Australia in the period of 12 months after the date of allotment under the offering, except in circumstances where disclosure to investors under Chapter 6D of the Corporations Act would not be required pursuant to an exemption under section 708 of the Corporations Act or otherwise or where the offer is pursuant to a disclosure document which complies with Chapter 6D of the Corporations Act. Any person acquiring common shares must observe such Australian on-sale restrictions.

          This prospectus supplement and accompanying prospectus contains general information only and does not take account of the investment objectives, financial situation or particular needs of any particular person. It does not contain any securities recommendations or financial product advice. Before making an investment decision, investors need to consider whether the information in this prospectus supplement and accompanying prospectus is appropriate to their needs, objectives and circumstances, and, if necessary, seek expert advice on those matters.

Notice to Prospective Investors in the Dubai International Financial Centre

          This prospectus supplement and accompanying prospectus relates to an Exempt Offer in accordance with the Offered Securities Rules of the Dubai Financial Services Authority ("DFSA"). This prospectus supplement and accompanying prospectus is intended for distribution only to persons of a type specified in the Offered Securities Rules of the DFSA. It must not be delivered to, or relied on by, any other person. The DFSA has no responsibility for reviewing or verifying any documents in connection with Exempt Offers. The DFSA has not approved this prospectus supplement and accompanying prospectus nor taken steps to verify the information set forth herein and has no responsibility for the prospectus supplement and accompanying prospectus. The common shares to which this prospectus supplement and accompanying prospectus relates may be illiquid and/or subject to restrictions on their resale. Prospective purchasers of the common shares offered should conduct their own due diligence on the shares. If you do not understand the contents of this prospectus supplement and accompanying prospectus you should consult an authorized financial advisor.

Notice to Prospective Investors in the European Economic Area

          In relation to each Member State of the European Economic Area (each, a "Relevant Member State"), no offer of common shares may be made to the public in that Relevant Member State other than:

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provided that no such offer of common shares shall require the Company or the representatives to publish a prospectus pursuant to Article 3 of the Prospectus Directive or supplement a prospectus pursuant to Article 16 of the Prospectus Directive.

          Each person in a Relevant Member State who initially acquires any common shares or to whom any offer is made will be deemed to have represented, acknowledged and agreed that it is a "qualified investor" within the meaning of the law in that Relevant Member State implementing Article 2(1)(e) of the Prospectus Directive. In the case of any common shares being offered to a financial intermediary as that term is used in Article 3(2) of the Prospectus Directive, each such financial intermediary will be deemed to have represented, acknowledged and agreed that the common shares acquired by it in the offer have not been acquired on a non-discretionary basis on behalf of, nor have they been acquired with a view to their offer or resale to, persons in circumstances which may give rise to an offer of any shares to the public other than their offer or resale in a Relevant Member State to qualified investors as so defined or in circumstances in which the prior consent of the representatives has been obtained to each such proposed offer or resale.

          The Company, the representatives and their affiliates will rely upon the truth and accuracy of the foregoing representations, acknowledgements and agreements.

          This prospectus supplement and accompanying prospectus has been prepared on the basis that any offer of common shares in any Relevant Member State will be made pursuant to an exemption under the Prospectus Directive from the requirement to publish a prospectus for offers of common shares. Accordingly any person making or intending to make an offer in that Relevant Member State of common shares which are the subject of the offering contemplated in this prospectus supplement and accompanying prospectus may only do so in circumstances in which no obligation arises for the Company or the underwriters to publish a prospectus pursuant to Article 3 of the Prospectus Directive in relation to such offer. Neither the Company nor the underwriters have authorized, nor do they authorize, the making of any offer of common shares in circumstances in which an obligation arises for the Company or the underwriters to publish a prospectus for such offer.

          For the purpose of the above provisions, the expression "an offer to the public" in relation to any common shares in any Relevant Member State means the communication in any form and by any means of sufficient information on the terms of the offer and the shares to be offered so as to enable an investor to decide to purchase or subscribe the common shares, as the same may be varied in the Relevant Member State by any measure implementing the Prospectus Directive in the Relevant Member State and the expression "Prospectus Directive" means Directive 2003/71/EC (including the 2010 PD Amending Directive, to the extent implemented in the Relevant Member States) and includes any relevant implementing measure in the Relevant Member State and the expression "2010 PD Amending Directive" means Directive 2010/73/EU.

Notice to Prospective Investors in Hong Kong

          The common shares have not been offered or sold and will not be offered or sold in Hong Kong, by means of any document, other than (a) to "professional investors" as defined in the Securities and Futures Ordinance (Cap. 571) of Hong Kong and any rules made under that Ordinance; or (b) in other circumstances which do not result in the document being a "prospectus" as defined in the Companies Ordinance (Cap. 32) of Hong Kong or which do not constitute an offer to the public within the meaning of that Ordinance. No advertisement, invitation or document relating to the common shares has been or may be issued or has been or may be in the possession of any person for the purposes of issue, whether in Hong Kong or elsewhere, which is directed at, or the contents of which are likely to be accessed or read by, the public of Hong Kong (except if permitted to do so under the securities laws of Hong Kong) other than with respect to common shares which are or are intended to be disposed of only to persons outside Hong Kong or only to "professional investors" as defined in the Securities and Futures Ordinance and any rules made under that Ordinance.

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Notice to Prospective Investors in Switzerland

          We have not and will not register with the Swiss Financial Market Supervisory Authority ("FINMA") as a foreign collective investment scheme pursuant to Article 119 of the Federal Act on Collective Investment Scheme of 23 June 2006, as amended ("CISA"), and accordingly the securities being offered pursuant to this prospectus have not and will not be approved, and may not be licensable, with FINMA. Therefore, the securities have not been authorized for distribution by FINMA as a foreign collective investment scheme pursuant to Article 119 CISA and the securities offered hereby may not be offered to the public (as this term is defined in Article 3 CISA) in or from Switzerland. The securities may solely be offered to "qualified investors," as this term is defined in Article 10 CISA, and in the circumstances set out in Article 3 of the Ordinance on Collective Investment Scheme of 22 November 2006, as amended ("CISO"), such that there is no public offer. Investors, however, do not benefit from protection under CISA or CISO or supervision by FINMA. This prospectus and any other materials relating to the securities are strictly personal and confidential to each offeree and do not constitute an offer to any other person. This prospectus may only be used by those qualified investors to whom it has been handed out in connection with the offer described herein and may neither directly or indirectly be distributed or made available to any person or entity other than its recipients. It may not be used in connection with any other offer and shall in particular not be copied and/or distributed to the public in Switzerland or from Switzerland. This prospectus does not constitute an issue prospectus as that term is understood pursuant to Article 652a and/or 1156 of the Swiss Federal Code of Obligations. We have not applied for a listing of the securities on the SIX Swiss Exchange or any other regulated securities market in Switzerland, and consequently, the information presented in this prospectus does not necessarily comply with the information standards set out in the listing rules of the SIX Swiss Exchange and corresponding prospectus schemes annexed to the listing rules of the SIX Swiss Exchange.

Notice to Prospective Investors in the United Kingdom

          In addition, in the United Kingdom, this document is being distributed only to, and is directed only at, and any offer subsequently made may only be directed at persons who are "qualified investors" (as defined in the Prospectus Directive) (i) who have professional experience in matters relating to investments falling within Article 19 (5) of the Financial Services and Markets Act 2000 (Financial Promotion) Order 2005, as amended (the "Order") and/or (ii) who are high net worth companies (or persons to whom it may otherwise be lawfully communicated) falling within Article 49(2)(a) to (d) of the Order (all such persons together being referred to as "relevant persons"). This document must not be acted on or relied on in the United Kingdom by persons who are not relevant persons. In the United Kingdom, any investment or investment activity to which this document relates is only available to, and will be engaged in with, relevant persons.

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LEGAL MATTERS

          The validity of the common shares offered hereby, as well as certain legal matters relating to us, will be passed upon for us by Pepper Hamilton LLP. Certain legal matters related to the offering will be passed upon for the underwriters by Hunton & Williams LLP.

EXPERTS

          The consolidated financial statements and financial statement schedules of CubeSmart and CubeSmart, L.P. as of December 31, 2013 and 2012 and for each of the years in the three-year period ended December 31, 2013 and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2013 have been incorporated by reference herein in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

          We incorporate information into this prospectus supplement and the accompanying prospectus by reference, which means that we disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus supplement and the accompanying prospectus, except to the extent superseded by information contained herein or by information contained in documents filed with the SEC after the date of this prospectus supplement and the accompanying prospectus. This prospectus supplement and the accompanying prospectus incorporate by reference the documents set forth below that have been previously filed with the SEC (other than, in each case, documents or information deemed to have been "furnished" and not "filed" in accordance with SEC rules):

          We also incorporate by reference into this prospectus supplement and the accompanying prospectus additional documents that we may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act, from the date of this prospectus supplement until all of the securities offered by this prospectus supplement have been sold or we otherwise terminate the offering of these securities; provided, however, that we are not incorporating by reference any additional documents or information "furnished" and not "filed" with the SEC. You may obtain copies of any of these filings by contacting us at the following address and phone number or by contacting the SEC or NYSE as described above.

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Documents incorporated by reference are available from us without charge, excluding all exhibits unless an exhibit has been specifically incorporated by reference into this prospectus supplement or the accompanying prospectus, by requesting them in writing, by telephone or via the Internet at:

CubeSmart
Attention: Investor Relations
5 Old Lancaster Road
Malvern, PA 19355
Phone: (610) 535-5700
Internet Website: www.cubesmart.com

          The information contained on our website does not constitute a part of this prospectus supplement or the accompanying prospectus except to the extent otherwise expressly provided for herein and therein, and our website address supplied above is intended to be an inactive textual reference only and not an active hyperlink to our website.

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WHERE YOU CAN FIND MORE INFORMATION

          We are subject to the informational requirements of the Exchange Act. Accordingly, we file current, quarterly and annual reports, proxy statements and other information with the SEC. You may read and copy these reports, proxy statements and other information at the SEC's Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Please call 1-800-SEC-0330 for further information on the operation of the SEC's Public Reference Room. Our SEC filings also are available to the public at the Internet website maintained by the SEC at www.sec.gov and from commercial document retrieval services.

          We also make available free of charge through our website our filings with the SEC, including our annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act, definitive proxy statements and Section 16 reports on Forms 3, 4 and 5, as soon as reasonably practicable after we electronically file such reports or amendments with, or furnish them to, the SEC. Our Internet website address is www.cubesmart.com. The information located on, or hyperlinked or otherwise connected to, our website is not, and shall not be deemed to be, a part of this prospectus supplement or incorporated into any other filings that we make with the SEC. You may also inspect the information that we file with the NYSE, at the offices of the NYSE located at 20 Broad Street, New York, New York 10005.

          We have filed with the SEC a registration statement on Form S-3 (Registration File No. 333-194661) covering the common shares offered by this prospectus supplement and the accompanying prospectus. You should be aware that this prospectus supplement and related prospectus do not contain all of the information contained or incorporated by reference in that registration statement and its exhibits and schedules. You may inspect and obtain the registration statement, including exhibits, schedules, reports and other information that we have filed with the SEC, as described in the preceding paragraph. Statements contained in this prospectus supplement concerning the contents of any document we refer you to are not necessarily complete and in each instance we refer you to the applicable document filed with the SEC for more complete information.

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PROSPECTUS
CUBESMART
Common Shares
Preferred Shares
Depositary Shares
Subscription Rights
Warrants
Guarantees



CUBESMART, L.P.
Debt Securities



        CubeSmart may from time to time offer, in one or more classes or series, separately or together, and in amounts, at prices and on terms to be set forth in one or more supplements to this prospectus, the following securities:

        CubeSmart, L.P. may from time to time offer, in one or more classes or series, separately or together, and in amounts, at prices and on terms to be set forth in one or more supplements to this prospectus, its debt securities. CubeSmart will unconditionally guarantee the payment obligations of the debt securities of CubeSmart, L.P.

        We refer to the common shares, preferred shares, depositary shares, subscription rights, warrants and guarantees of CubeSmart, together with the debt securities of CubeSmart, L.P. collectively as the "securities."

        The common shares of CubeSmart are listed on the New York Stock Exchange, or NYSE, under the symbol "CUBE."

        Investing in the securities involves risks that are described on page 6 of this prospectus. You should carefully read and consider this prospectus, the applicable prospectus supplement and the risk factors included in the applicable prospectus supplement and/or in our periodic reports and other information that we file with the Securities and Exchange Commission before investing in the securities.

        Neither the Securities and Exchange Commission nor any state securities regulators have approved or disapproved these securities, or determined if this prospectus is truthful or complete. Any representation to the contrary is a criminal offense.

This prospectus is dated March 18, 2014.



TABLE OF CONTENTS

ABOUT THIS PROSPECTUS

    1  

WHERE YOU CAN FIND MORE INFORMATION

   
1
 

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

   
1
 

FORWARD-LOOKING STATEMENTS

   
3
 

CUBESMART AND THE OPERATING PARTNERSHIP

   
5
 

RISK FACTORS

   
6
 

USE OF PROCEEDS

   
6
 

RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO COMBINED FIXED CHARGES AND PREFERENCE DIVIDENDS

   
7
 

DESCRIPTION OF CUBESMART'S CAPITAL SHARES

   
8
 

DESCRIPTION OF DEPOSITARY SHARES

   
17
 

DESCRIPTION OF SUBSCRIPTION RIGHTS

   
20
 

DESCRIPTION OF WARRANTS

   
21
 

DESCRIPTION OF THE DEBT SECURITIES

   
23
 

MATERIAL FEDERAL INCOME TAX CONSIDERATIONS

   
38
 

PLAN OF DISTRIBUTION

   
71
 

LEGAL MATTERS

   
73
 

EXPERTS

   
73
 

        You should rely only on the information provided or incorporated by reference into this prospectus or any applicable prospectus supplement. We have not authorized anyone to provide you with different or additional information. This prospectus does not constitute an offer to sell or a solicitation of an offer to buy by anyone in any jurisdiction in which such offer to sell is not authorized, or in which the person is not qualified to do so or to any person to whom it is unlawful to make such offer or solicitation. You should not assume that the information included in this prospectus, any prospectus supplement, or the documents incorporated by reference herein or therein is accurate as of any date other than the date of this prospectus, any prospectus supplement or incorporated document, as applicable. Our business, financial condition, results of operations and prospects may have changed since those dates.

i


ABOUT THIS PROSPECTUS

        This prospectus is part of a universal shelf registration statement on Form S-3 that we filed with the Securities and Exchange Commission, or the SEC, under the Securities Act of 1933, as amended, or the Securities Act. To the extent required for any offer and sale, a prospectus supplement will set forth the type and number of securities being offered, the offering price, the names of any underwriters, dealers, brokers or agents and the applicable sales commission or discount. The prospectus supplement may also add, update or change information contained in this prospectus. You should read carefully the entire prospectus and any prospectus supplement, as well as the documents incorporated by reference into this prospectus and/or any prospectus supplement, before making an investment decision.

        This prospectus and any accompanying prospectus supplement do not contain all of the information included in the registration statement. For further information, we refer you to the registration statement, including the exhibits. Statements contained in this prospectus and any accompanying prospectus supplement about the provisions or contents of any agreement or other document are not necessarily complete. If the rules and regulations of the SEC require that such agreement or document be filed as an exhibit to the registration statement, please see such agreement or document for a complete description of these matters.

        As used in this prospectus and the registration statement on Form S-3 of which this prospectus is a part, unless the context otherwise requires, references to "CubeSmart" refer to CubeSmart, a Maryland real estate investment trust, or "REIT"; references to the "Operating Partnership" refer to CubeSmart, L.P., a Delaware limited partnership; and references to "we," "us," "our" or similar expressions refer collectively to CubeSmart and its consolidated subsidiaries (including the Operating Partnership).

WHERE YOU CAN FIND MORE INFORMATION

        We are subject to the informational requirements of the Securities Exchange Act of 1934, as amended, or the Exchange Act. Accordingly, we file current, quarterly and annual reports, proxy statements and other information with the SEC. You may read and copy these reports, proxy statements and other information at the SEC's Public Reference Room at 100 F Street, N.E., Washington, D.C. 20549. Please call 1-800-SEC-0330 for further information on the operation of the SEC's Public Reference Room. Our SEC filings also are available to the public at the Internet website maintained by the SEC at www.sec.gov and from commercial document retrieval services.

        We also make available free of charge through our website the filings made by CubeSmart and the Operating Partnership with the SEC, including the Operating Partnership's Registration Statement on Form 10, as amended, and CubeSmart's and the Operating Partnership's annual report on Form 10-K, quarterly reports on Form 10-Q, current reports on Form 8-K, and amendments to those reports filed or furnished pursuant to Section 13(a) or 15(d) of the Exchange Act, and CubeSmart's definitive proxy statements and Section 16 reports on Forms 3, 4 and 5, as soon as reasonably practicable after we electronically file such reports or amendments with, or furnish them to, the SEC. Our Internet website address is www.cubesmart.com. The information located on, or hyperlinked or otherwise connected to, our website is not, and shall not be deemed to be, a part of this prospectus or incorporated into any other filings that we make with the SEC. You may also inspect the information that we file with the NYSE, at the offices of the NYSE located at 20 Broad Street, New York, New York 10005.

INCORPORATION OF CERTAIN INFORMATION BY REFERENCE

        We incorporate information into this prospectus by reference, which means that we disclose important information to you by referring you to another document filed separately with the SEC. The information incorporated by reference is deemed to be part of this prospectus, except to the extent superseded by information contained herein or by information contained in documents filed with the SEC after the date of this prospectus. This prospectus incorporates by reference the documents set


forth below that have been previously filed with the SEC (other than, in each case, documents or information deemed to have been "furnished" and not "filed" in accordance with SEC rules):

        We also incorporate by reference into this prospectus additional documents that we may file with the SEC under Section 13(a), 13(c), 14 or 15(d) of the Exchange Act, from the date of this prospectus until all of the securities offered by this prospectus have been sold or we otherwise terminate the offering of these securities; provided, however, that we are not incorporating by reference any additional documents or information "furnished" and not "filed" with the SEC. You may obtain copies of any of these filings by contacting us at the following address and phone number or by contacting the SEC or NYSE as described above. Documents incorporated by reference are available from us without charge, excluding all exhibits unless an exhibit has been specifically incorporated by reference into this prospectus, by requesting them in writing, by telephone or via the Internet at:

CubeSmart
Attention: Investor Relations
5 Old Lancaster Road
Malvern, PA 19355
Phone: (610) 535-5000
Internet Website:
www.cubesmart.com

        The information contained on our website does not constitute a part of this prospectus, and our website address supplied above is intended to be an inactive textual reference only and not an active hyperlink to our website.

        You should rely only on the information contained or incorporated by reference in this prospectus, the prospectus supplement, any free writing prospectus that we authorize and any pricing supplement. We have not authorized any person, including any salesman or broker, to provide information other than that provided in this prospectus, any applicable prospectus supplement, any free writing prospectus that we authorize or any pricing supplement. We have not authorized anyone to provide you with different information. We do not take responsibility for, and can provide no assurance as to the reliability of, any information that others may give you. We are not making an offer of the securities in any jurisdiction where the offer is not permitted. You should assume that the information in this prospectus, any applicable prospectus supplement, any free writing prospectus that we authorize and any pricing supplement is accurate only as of the date on its cover page and that any information we have incorporated by reference is accurate only as of the date of such document incorporated by reference.

2


        Any statement contained in a document incorporated or deemed to be incorporated by reference into this prospectus will be deemed to be modified or superseded for purposes of this prospectus to the extent that a statement contained in this prospectus, any prospectus supplement, or any other subsequently filed document that is deemed to be incorporated by reference into this prospectus modifies or supersedes the statement. Any statement so modified or superseded will not be deemed, except as so modified or superseded, to constitute a part of this prospectus.

FORWARD-LOOKING STATEMENTS

        This prospectus and any accompanying prospectus supplement, together with other documents and information incorporated by reference into this prospectus, contain certain forward-looking statements within the meaning of Section 27A of the Securities Act of 1933 and Section 21E of the Securities Exchange Act of 1934, as amended (the "Exchange Act"). Such statements are based on assumptions and expectations that may not be realized and are inherently subject to risks, uncertainties and other factors, many of which cannot be predicted with accuracy and some of which might not even be anticipated. Although we believe the expectations reflected in these forward-looking statements are based on reasonable assumptions, future events and actual results, performance, transactions or achievements, financial and otherwise, may differ materially from the results, performance, transactions or achievements expressed or implied by the forward-looking statements contained in or contemplated by this prospectus or any prospectus supplement. Any forward-looking statements should be considered in light of the risks and uncertainties referred to in Item 1A. "Risk Factors" in CubeSmart's and the Operating Partnership's Annual Report on Form 10-K for the year ended December 31, 2013. The most significant of these risks, uncertainties and other factors that might cause such differences include, but are not limited to:

3


        In light of these uncertainties and risks, prospective investors are cautioned not to place undue reliance on these forward-looking statements. Except with respect to such material changes to our risk factors as may be reflected from time to time in our quarterly filings or as otherwise required by law, we are under no obligation to, and expressly disclaim any obligation to, update or revise any forward-looking statements included or incorporated by reference in this prospectus or any accompanying prospectus supplement, whether as a result of new information, future events or otherwise. Because of the factors referred to above, the future events discussed in or incorporated by reference in this prospectus or any accompanying prospectus supplement may not occur and actual results, performance or achievement could differ materially from that anticipated or implied in the forward-looking statements.

4


CUBESMART AND THE OPERATING PARTNERSHIP

        CubeSmart is a self-administered and self-managed real estate investment trust, or REIT, focused primarily on the ownership, operation, management, acquisition and development of self-storage facilities in the United States. CubeSmart was organized and commenced operations in 2004 as a Maryland REIT. The Operating Partnership was formed and commenced operations in 1996 as a Delaware limited partnership.

        CubeSmart owns its assets, and conducts its operations, through the Operating Partnership. CubeSmart controls the Operating Partnership as its sole general partner and, as of March 13, 2014, CubeSmart owned an approximately 98.45% interest in the Operating Partnership. The Operating Partnership has been engaged in virtually all aspects of the self-storage business, including the development, acquisition, management, ownership and operation of self-storage facilities.

        Our self-storage facilities are designed to offer affordable and easily-accessible storage space for our residential and commercial customers. Our customers rent storage units for their exclusive use, typically on a month-to-month basis. Additionally, some of our facilities offer outside storage areas for vehicles and boats. Our facilities are designed to accommodate both residential and commercial customers, with features such as security systems and wide aisles and load-bearing capabilities for large truck access. All of our facilities have an on-site manager during business hours, and many have a manager who resides in an apartment at the facility. Our customers can access their storage units during business hours, and some of our facilities provide customers with 24-hour access through computer controlled access systems. Our goal is to provide customers with the highest standard of facilities and service in the industry. To that end, as of December 31, 2013, a majority of our facilities included climate controlled units.

        Our executive offices are located at 5 Old Lancaster Road, Malvern, PA 19355 and our telephone number is (610) 535-5000.

5


RISK FACTORS

        Investing in our securities involves risks. You should carefully consider the risk factors incorporated by reference to our most recent Annual Report on Form 10-K and the other information contained or incorporated by reference in this prospectus, as updated by our subsequent filings under the Exchange Act, and the risk factors and other information contained in the applicable prospectus supplement before acquiring any of such securities. The occurrence of any of these risks might cause you to lose all or part of your investment in the offered securities. Please also refer to the section above entitled "Forward-Looking Statements."

USE OF PROCEEDS

        Unless otherwise indicated in the applicable prospectus supplement, CubeSmart will contribute or otherwise transfer the net proceeds of any sale of securities to the Operating Partnership in exchange for additional partnership interests in the Operating Partnership, the economic terms of which will be substantially identical to those of the securities sold.

        Unless otherwise indicated in the applicable prospectus supplement, the Operating Partnership will use those net proceeds and any net proceeds from any sale of its debt securities for general business purposes, including, without limitation, repayment of outstanding debt, acquisitions, developments, capital expenditures, working capital and other general corporate purposes.

6


RATIO OF EARNINGS TO FIXED CHARGES AND RATIO OF EARNINGS TO COMBINED FIXED
CHARGES AND PREFERENCE DIVIDENDS

Ratio of Earnings to Fixed Charges

        The following table sets forth the Operating Partnership's ratios of earnings to fixed charges for the periods indicated.

 
  For the years ended December 31,  
 
  2013   2012   2011   2010   2009  

Ratio of earnings to fixed charges(a)

    1.22     0.70     0.71     0.61     0.47  

For the purpose of calculating the ratio of earnings to fixed charges, earnings consist of income (loss) from continuing operations, plus fixed charges less capitalized interest. Fixed charges consist of interest expense, capitalized interest, amortized premiums, discounts and capitalized expenses relating to debt and an estimate of the interest component of rent expense.

(a)
In fiscal 2009, 2010, 2011 and 2012, earnings were insufficient to cover fixed charges. The Operating Partnership must generate additional earnings of $25.4 million, $17.6 million, $13.5 million and $13.5 million to achieve a fixed charge coverage ratio of 1:1 in fiscal 2009, 2010, 2011 and 2012, respectively.

Ratio of Earnings to Combined Fixed Charges and Preference Dividends

        The following table sets forth CubeSmart's ratios of earnings to combined fixed charges and preference dividends for the periods indicated.

 
  For the years ended
December 31,
 
 
  2013   2012   2011   2010   2009  

Ratio of earnings to combined fixed charges and preference dividends(a)

    1.07     0.61     0.69     0.61     0.47  

For the purpose of calculating the ratio of earnings to combined fixed charges and preference dividends, earnings consist of income (loss) from continuing operations, plus fixed charges less capitalized interest. Fixed charges consist of interest expense, capitalized interest, amortized premiums, discounts and capitalized expenses relating to debt and an estimate of the interest component of rent expense. Preference dividends includes income allocated to holders of CubeSmart's preferred shares.

(a)
In fiscal 2009, 2010, 2011 and 2012, earnings were insufficient to cover combined fixed charges and preference dividends. CubeSmart must generate additional earnings of $25.4 million, $17.6 million, $14.7 million and $19.5 million to achieve a coverage ratio of 1:1 in fiscal 2009, 2010, 2011 and 2012, respectively.

7


DESCRIPTION OF CUBESMART'S CAPITAL SHARES

        The following description of our capital shares, together with the additional information we include in any applicable prospectus supplement, summarizes the material terms and provisions of the capital shares that may be offered under this prospectus. For the complete terms of our capital shares, please refer to our declaration of trust and bylaws that are filed as exhibits to our reports incorporated by reference into the registration statement of which this prospectus is a part. See "Where You Can Find More Information."

Common Shares

        CubeSmart's declaration of trust provides that CubeSmart may issue up to 200,000,000 common shares of beneficial interest, par value $0.01 per share. As of February 25, 2014, there were 140,289,967 common shares issued and outstanding.

        Both Maryland statutory law governing real estate investment trusts formed under Maryland law, which we refer to as the Maryland REIT Law, and CubeSmart's declaration of trust provide that none of its shareholders will be personally liable, by reason of status as a shareholder, for any of its obligations.

        Subject to the provisions of CubeSmart's declaration of trust regarding restrictions on the transfer and ownership of shares of beneficial interest, each outstanding common share entitles the holder to one vote on all matters submitted to a vote of shareholders, including the election of trustees, and, except as provided with respect to any other class or series of shares of beneficial interest that CubeSmart may issue, the holders of such common shares will possess exclusive voting power. There is no cumulative voting in the election of trustees. As a result, the holders of a majority of the outstanding common shares, voting as a single class, can elect all of the trustees then standing for election. CubeSmart's bylaws provide that a plurality of the votes case at a meeting of shareholders duly called at which a quorum is present is sufficient to elect a trustee and that a majority of the votes cast at a meeting of shareholders duly called at which a quorum is present is sufficient to approve any other matter which may properly come before the meeting, unless a higher vote is required under CubeSmart's bylaws, CubeSmart's declaration of trust or applicable statute.

        Under the Maryland REIT law, a Maryland REIT generally cannot amend its declaration of trust or merge with another entity without the affirmative vote of shareholders holding at least two-thirds of the shares entitled to vote on the matter unless a lesser percentage (but not less than a majority of all the votes entitled to be cast on the matter) is set forth in the REIT's declaration of trust. Our declaration of trust provides that amendments to the declaration of trust and our merger with another entity may be approved by the affirmative vote of the holders of not less than a majority of all votes entitled to be cast on the matter. Under the Maryland REIT law and CubeSmart's declaration of trust, its trustees will be permitted to amend the declaration of trust from time to time to maintain our qualification as a REIT under the Internal Revenue Code of 1986, as amended, or the Code, and under the Maryland REIT law, without the affirmative vote or written consent of the shareholders.

        All common shares offered by this prospectus will be duly authorized, fully paid and nonassessable. Holders of CubeSmart's common shares are entitled to receive dividends and distributions when authorized by our board of trustees, and declared by CubeSmart out of assets legally available for the payment of dividends or distributions. They also are entitled to share ratably in CubeSmart's assets legally available for distribution to its shareholders in the event of CubeSmart's liquidation, dissolution or winding up, after payment of or adequate provision for all of its known debts and liabilities. These rights are subject to the preferential rights of the holders of the 7.75% Series A Preferred Shares and of any other class or series of CubeSmart's shares and to the provisions of CubeSmart's declaration of trust regarding restrictions on transfer of its shares.

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        Holders of CubeSmart's common shares have no preference, conversion, exchange, sinking fund, redemption or appraisal rights and have no preemptive rights to subscribe for any of our securities. Subject to the restrictions on transfer of shares contained in CubeSmart's declaration of trust and to the power of the board of trustees to create common shares with differing voting rights, all common shares have equal dividend, liquidation and other rights.

Preferred Shares

        CubeSmart's declaration of trust provides that it may issue up to 40,000,000 preferred shares of beneficial interest, par value $0.01 per share. As of February 25, 2014, there were 3,220,000 authorized shares of CubeSmart's 7.75% Series A Preferred Shares, par value $0.01 par value, of which 3,100,000 were issued and outstanding.

        Holders of 7.75% Series A Preferred Shares do not have voting rights except (1) with respect to certain actions which would have a material adverse effect on the holders of such shares (including in a merger or consolidation) or (2) in the event we fail to pay quarterly distributions for six or more quarters to the holders of the 7.75% Series A Preferred Shares. If the conditions specified in (2) exist, the holders of 7.75% Series A Preferred Shares will have the right, voting as a single class with any other series of CubeSmart's preferred shares ranking on a parity with the 7.75% Series A Preferred Shares and upon which like voting rights have been conferred, to elect two additional members to CubeSmart's board of trustees.

        The holders of 7.75% Series A Preferred Shares will be entitled to receive, when and as authorized by CubeSmart's board of trustees, cumulative preferential cash distributions at the rate of 7.75% per annum of the $25.00 per share liquidation preference of the shares. Upon dissolution or liquidation, the holders of 7.75% Series A Preferred Shares will be entitled to be paid a liquidation preference in cash of $25.00 per share plus all accumulated and unpaid distributions after payment or provision for payment of all debts and liabilities of CubeSmart but before any distribution of assets is made to holders of common shares or any other junior securities of CubeSmart as to liquidation rights.

        CubeSmart's board of trustees is authorized to issue the preferred shares in one or more series and to fix and designate the rights, preferences, privileges and restrictions of the preferred shares, including:

        The rights, preferences, privileges and restrictions of the preferred shares of each series will be fixed by articles supplementary relating to each series. We will describe the specific terms of a particular series of preferred shares in the prospectus supplement relating to that series, including:

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        The description of preferred shares above and the description of the terms of a particular series of preferred shares in the prospectus supplement are not complete. You should refer to the applicable articles supplementary for complete information.

        CubeSmart's board of trustees could authorize, without shareholder approval, the issuance of preferred shares with terms and conditions that could have the effect of discouraging a takeover or other transaction in which holders of some or a majority of CubeSmart's shares might receive a premium for their shares over the then-prevailing market price of its shares. We currently do not expect that the board of trustees would require shareholder approval prior to such a preferred issuance. In addition, any preferred shares that CubeSmart issues would rank senior to its common shares with respect to the payment of distributions, in which case CubeSmart could not pay any distributions on its common shares until full distributions have been paid with respect to such preferred shares.

Power to Reclassify Shares and Issue Additional Common Shares or Preferred Shares

        CubeSmart's declaration of trust authorizes its board of trustees to classify any authorized but unissued common and preferred shares and to reclassify any previously classified but unissued common shares and preferred shares of any series from time to time in one or more series, as authorized by the board of trustees. Prior to the issuance of shares of each class or series, the board of trustees is required by the Maryland REIT law and CubeSmart's declaration of trust to establish for each such class or series, subject to the provisions of CubeSmart's declaration of trust regarding the restrictions on transfer of shares of beneficial interest, the terms, preferences, conversion or other rights, voting powers, restrictions, limitations as to dividends or other distributions, qualifications and terms or conditions of redemption for each such class or series. As a result, CubeSmart's board of trustees could authorize the issuance of preferred shares that have priority over the common shares with respect to dividends, distributions and rights upon liquidation and with other terms and conditions that could have

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the effect of delaying, deterring or preventing a transaction or a change in control that might involve a premium price for holders of common shares or otherwise might be in their best interest.

        To permit us increased flexibility in structuring possible future financings and acquisitions and in meeting other needs that might arise, CubeSmart's declaration of trust allows us to issue additional common shares or preferred shares and to classify or reclassify unissued common shares or preferred shares and thereafter to issue the classified or reclassified shares without shareholder approval, unless shareholder approval is required by applicable law or the rules of any stock exchange or automated quotation system on which CubeSmart's securities may be listed or traded. Although we have no present intention of doing so, we could issue a class or series of shares that could delay, deter or prevent a transaction or a change in control that might involve a premium price for holders of common shares or might otherwise be in their best interests.

        Holders of CubeSmart's 7.75% Series A Preferred Shares have the right to consent to the authorization, creation or issuance of equity securities that would rank senior to the 7.75% Series A Preferred Shares as to distributions or upon liquidation and the authorization, creation or issuance of convertible securities or obligations convertible into such senior securities, in each case, if such equity securities or convertible securities would materially or adversely affect the rights, preferences, privileges or voting powers of the 7.75% Series A Preferred Shares. This consent right shall not apply to the authorization, creation or issuance of equity securities on a parity with or junior to the 7.75% Series A Preferred Shares or to any increase in the number of 7.75% Series A Preferred Shares.

        Holders of CubeSmart's common shares or 7.75% Series A Preferred Shares do not have preemptive rights, which means they have no right to acquire any additional shares that we may issue at a subsequent date.

Restrictions on Ownership and Transfer

        In order to qualify as a REIT under the Code, CubeSmart's shares must be beneficially owned by 100 or more persons during at least 335 days of a taxable year of 12 months or during a proportionate part of a shorter taxable year. Also, no more than 50% of the value of CubeSmart's outstanding shares (after taking into account options to acquire shares) may be owned, directly, indirectly or through attribution, by five or fewer individuals (as defined in the Code to include certain entities).

        Because CubeSmart's board of trustees believes that it is in CubeSmart's shareholders' best interests to continue to qualify as a REIT and for anti-takeover and other strategic reasons, its declaration of trust, subject to certain exceptions, contains restrictions on the number of CubeSmart's shares of beneficial interest that a person may own. CubeSmart's declaration of trust provides that:

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        The excepted holder limit was established in light of the fact that Robert J. Amsdell, Barry L. Amsdell, Todd C. Amsdell and certain Amsdell Entities owned a substantial percentage of CubeSmart's common shares upon completion of its IPO. The excepted holder limit does not permit each excepted holder to own 29% of CubeSmart's common shares. Rather, the excepted holder limit prevents two or more excepted holders who are each treated as individuals under the applicable tax attribution rules from owning a higher percentage of CubeSmart's common shares than the maximum number of common shares that could be owned by any one excepted holder (29%), plus the maximum number of common shares that could be owned by any one or more other individual common shareholders who are not excepted holders (5%). We do not believe the 29% expected holder limit for certain members of the Amsdell family and certain related entities will jeopardize CubeSmart's REIT status because no other individual shareholder can own more than 5% of the value of CubeSmart's outstanding common shares. Accordingly, no five individuals can own more than 49% of CubeSmart's shares and, thus, we will be in compliance with the REIT qualification requirement prohibiting five or fewer individuals from owning more than 50% of the value of CubeSmart's outstanding shares.

        The declaration of trust defines a "designated investment entity" as:

        CubeSmart's board of trustees may waive the 5% ownership limit, or the 9.8% designated investment entity limit, for a shareholder that is not an individual if such shareholder provides information and makes representations to the board of trustees that are satisfactory to the board of

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trustees, in its reasonable discretion, to establish that such person's ownership in excess of the 5% limit or the 9.8% limit, as applicable, would not jeopardize CubeSmart's qualification as a REIT.

        Any person who acquires or attempts or intends to acquire beneficial or constructive ownership of CubeSmart's shares that will or may violate any of the foregoing restrictions on transferability and ownership will be required to give notice immediately to us and provide us with such other information as we may request in order to determine the effect of such transfer on CubeSmart's status as a REIT. If any transfer of shares or any other event would otherwise result in any person violating the ownership limits described above, then CubeSmart's declaration of trust provides that (a) the transfer will be void and of no force or effect with respect to the prohibited transferee with respect to that number of shares that exceeds the ownership limits or that such number of shares will be automatically transferred to a charitable trust for the benefit of a charitable beneficiary and (b) the prohibited transferee would not acquire any right or interest in the shares. The foregoing restrictions on transferability and ownership will not apply if CubeSmart's board of trustees determines that it is no longer in CubeSmart's best interests to attempt to qualify, or to continue to qualify, as a REIT.

        All certificates evidencing CubeSmart's shares bear a legend referring to the restrictions described above.

        Every owner of more than 5% (or such lower percentage as required by the Code or the regulations promulgated thereunder) of all classes or series of CubeSmart's shares, including common shares, is required to give written notice to us within 30 days after the end of each taxable year stating the name and address of such owner, the number of shares of each class and series of shares that the owner beneficially owns and a description of the manner in which such shares are held. Each such owner shall provide to us such additional information as we may request in order to determine the effect, if any, of such beneficial ownership on CubeSmart's status as a REIT and to ensure compliance with the ownership limitations. In addition, each shareholder shall upon demand be required to provide to us such information as we may request, in good faith, in order to determine CubeSmart's status as a REIT and to comply with the requirements of any taxing authority or governmental authority or to determine such compliance.

        These ownership limitations could delay, deter or prevent a transaction or a change in control that might involve a premium price for the common shares or might otherwise be in the best interest of CubeSmart's shareholders.

Transfer Agent and Registrar

        The transfer agent and registrar for our common shares is American Stock Transfer & Trust Co., LLC. The transfer agent and registrar for our preferred shares will be set forth in the applicable prospectus supplement.

Certain Provisions of Maryland Law and CubeSmart's Declaration of Trust and Bylaws

        The following description of certain provisions of Maryland law and of CubeSmart's declaration of trust and bylaws is only a summary. For a complete description, we refer you to the applicable Maryland law and CubeSmart declaration of trust and bylaws.

        CubeSmart's declaration of trust and bylaws provide that the number of CubeSmart's trustees shall not be less than one and not more than 13, and will be established by a vote of a majority of the members of its board of trustees. Our bylaws provide that any vacancy, including a vacancy created by an increase in the number of trustees, may be filled only by a majority of the remaining trustees, even if the remaining trustees do not constitute a quorum. Pursuant to CubeSmart's declaration of trust,

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each of its trustees is elected by its shareholders to serve until the next annual meeting and until their successors are duly elected and qualify. Under Maryland law, CubeSmart's board of trustees may elect to create staggered terms for its members.

        CubeSmart's bylaws provide that at least a majority of our trustees will be "independent," with independence being defined in the manner established by our board of trustees and in a manner consistent with listing standards established by the NYSE.

        In the event CubeSmart fails to pay quarterly distributions for six or more quarters to the holders of the 7.75% Series A Preferred Shares, the holders of 7.75% Series A Preferred Shares will have the right, voting as a single class with any other series of CubeSmart's preferred shares ranking on a parity with the 7.75% Series A Preferred Shares and upon which like voting rights have been conferred, to elect two additional members to CubeSmart's board of trustees.

        CubeSmart's declaration of trust provides that a trustee may be removed only with cause and only upon the affirmative vote of at least two-thirds of the votes entitled to be cast in the election of trustees. Absent removal of all of CubeSmart's trustees, this provision, when coupled with the provision in CubeSmart's bylaws authorizing CubeSmart's board of trustees to fill vacant trusteeships, may preclude shareholders from removing incumbent trustees and filling the vacancies created by such removal with their own nominees.

        CubeSmart's board of trustees has approved a resolution that exempts CubeSmart from the provisions of the Maryland business combination statute described below, but its board of trustees may opt to make these provisions applicable to CubeSmart in the future. Maryland law prohibits "business combinations" between CubeSmart and an interested shareholder (defined below) or an affiliate of an interested shareholder for five years after the most recent date on which the interested shareholder becomes an interested shareholder. These business combinations include a merger, consolidation, share exchange, or, in circumstances specified in the statute, an asset transfer or issuance or reclassification of equity securities. Maryland law defines an interested shareholder as:

A person is not an interested shareholder if CubeSmart's board of trustees approves in advance the transaction by which the person otherwise would have become an interested shareholder. However, in approving a transaction, CubeSmart's board of trustees may provide that its approval is subject to compliance, at or after the time of approval, with any terms and conditions determined by CubeSmart's board of trustees.

        After the five-year prohibition, any business combination between CubeSmart and an interested shareholder generally must be recommended by CubeSmart's board of trustees and approved by the affirmative vote of at least:

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These super-majority vote requirements do not apply if CubeSmart's common shareholders receive a minimum price, as described under Maryland law, for their shares in the form of cash or other consideration in the same form as previously paid by the interested shareholder for its shares.

        The statute permits various exemptions from its provisions, including business combinations that are approved by CubeSmart's board of trustees before the time that the interested shareholder becomes an interested shareholder.

        The consent of two-thirds of the holders of 7.75% Series A Preferred Shares outstanding at the time is required under certain circumstances for any amendment, alteration or repeal of CubeSmart's declaration of trust, including by merger or consolidation, which would materially and adversely affect any right, preference, privilege or voting power of the 7.75% Series A Preferred Shares unless such shares have been redeemed or called for redemption.

        Upon the occurrence of a change of control, the holders of 7.75% Series A Preferred Shares will have the right to convert their shares into common shares unless CubeSmart elects to redeem these shares in connection with such change of control.

        CubeSmart's bylaws contain a provision exempting any and all acquisitions of CubeSmart's shares from the provisions of the Maryland Control Share Acquisition Act. However, CubeSmart board of trustees may opt to make these provisions applicable to an acquisition of CubeSmart's shares at any time by amending or repealing this provision in the future, and may do so on a retroactive basis. Maryland law provides that "control shares" of a Maryland REIT acquired in a "control share acquisition" have no voting rights unless approved by a vote of two-thirds of the votes entitled to be cast on the matter. Shares beneficially owned by the acquiring person in a control share acquisition or by CubeSmart's officers or employees who are CubeSmart's trustees are excluded from the shares entitled to vote in accordance with the immediately preceding sentence. "Control shares" are shares that, if aggregated with all other shares previously acquired by the acquiring person, or in respect of which the acquiring person is able to exercise or direct the exercise of voting power (except solely by virtue of a revocable proxy), would entitle the acquiring person to exercise or direct the exercise of the voting power in electing trustees within one of the following ranges of voting power:

        Control shares do not include shares the acquiring person is then entitled to vote as a result of having previously obtained shareholder approval. A "control share acquisition" means the acquisition of control shares, subject to certain exceptions.

        A person who has made or proposes to make a control share acquisition may compel our board of trustees to call a special meeting of shareholders to be held within 50 days of demand to consider the voting rights of the shares. The right to compel the calling of a special meeting is subject to the satisfaction of certain conditions, including an undertaking to pay the expenses of the special meeting. If no request for a special meeting is made, we may present the question at any shareholders' meeting.

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        If voting rights are not approved at the shareholders' meeting or if the acquiring person does not deliver the statement required by Maryland law, then, subject to certain conditions and limitations, we may redeem any or all of the control shares, except those for which voting rights have previously been approved, for fair value. Fair value is determined without regard to the absence of voting rights for the control shares and as of the date of the last control share acquisition or of any meeting of shareholders at which the voting rights of the shares were considered and not approved. If voting rights for control shares are approved at a shareholders' meeting, the acquiror may then vote a majority of the shares entitled to vote, and all other shareholders may exercise appraisal rights. The fair value of the shares for purposes of these appraisal rights may not be less than the highest price per share paid by the acquiror in the control share acquisition. The control share acquisition statute does not apply to shares acquired in a merger, consolidation or share exchange if we are a party to the transaction, nor does it apply to acquisitions approved by or exempted by our declaration of trust or bylaws.

Possible Anti-Takeover Effect of Certain Provisions of Maryland Law and CubeSmart's Declaration of Trust and Bylaws

        The business combination provisions of Maryland law (if CubeSmart's board of trustees opts to make them applicable to CubeSmart), the control share acquisition provisions of Maryland law (if the applicable provision in CubeSmart's bylaws is rescinded), the limitations on removal of trustees, the restrictions on the acquisition of CubeSmart's shares of beneficial interest, the power to issue additional common shares or preferred shares and the advance notice provisions for shareholder trustee nominations and other shareholder proposals of our bylaws could have the effect of delaying, deterring or preventing a transaction or a change in control that might involve a premium price for holders of the common shares or might otherwise be in their best interest. The "unsolicited takeovers" provisions of Maryland law permit our board of trustees, without shareholder approval and regardless of what is provided in our declaration of trust or bylaws, to implement takeover defenses that we may not yet have.

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DESCRIPTION OF DEPOSITARY SHARES

General

        CubeSmart may elect to have shares of preferred shares represented by depositary shares. The shares of any series of the preferred shares underlying the depositary shares will be deposited under a separate deposit agreement between CubeSmart and a bank or trust company that we select. The prospectus supplement relating to a series of depositary shares will set forth the name and address of this preferred shares depositary. Subject to the terms of the deposit agreement, each owner of a depositary share will be entitled, proportionately, to all the rights, preferences and privileges of the preferred shares represented by such depositary share, including dividend, voting, redemption, conversion, exchange and liquidation rights. As of the date of this prospectus, there are no depositary shares outstanding.

        The depositary shares will be evidenced by depositary receipts issued pursuant to the deposit agreement, each of which will represent the applicable interest in a number of shares of a particular series of the preferred shares described in the applicable prospectus supplement.

        A holder of depositary shares will be entitled to receive the shares of preferred shares, but only in whole shares of preferred shares, underlying those depositary shares. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the whole number of shares of preferred shares to be withdrawn, the depositary will deliver to that holder at the same time a new depositary receipt for the excess number of depositary shares.

Dividends and Other Distributions

        The preferred shares depositary will distribute all cash dividends or other cash distributions in respect of the series of preferred shares represented by the depositary shares to the record holders of depositary receipts in proportion, to the extent possible, to the number of depositary shares owned by those holders. The depositary, however, will distribute only the amount that can be distributed without attributing to any depositary share a fraction of one cent, and any undistributed balance will be added to and treated as part of the next sum received by the depositary for distribution to record holders of depositary receipts then outstanding.

        If there is a distribution other than in cash in respect of the preferred shares, the preferred shares depositary will distribute property received by it to the record holders of depositary receipts in proportion, insofar as possible, to the number of depositary shares owned by those holders, unless the preferred shares depositary determines that it is not feasible to make such a distribution. In that case, the preferred shares depositary may, with our approval, adopt any method that it deems equitable and practicable to effect the distribution, including a public or private sale of the property and distribution of the net proceeds from the sale to the holders.

        The amount distributed in any of the above cases will be reduced by any amount we or the preferred shares depositary are required to withhold on account of taxes.

Conversion and Exchange

        If any series of preferred shares underlying the depositary shares is subject to provisions relating to its conversion or exchange as set forth in an applicable prospectus supplement, each record holder of depositary receipts will have the right or obligation to convert or exchange the depositary shares evidenced by the depositary receipts pursuant to those provisions.

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Redemption of Depositary Shares

        If any series of preferred shares underlying the depositary shares is subject to redemption, the depositary shares will be redeemed from the proceeds received by the preferred shares depositary resulting from the redemption, in whole or in part, of the preferred shares held by the preferred shares depositary. Whenever CubeSmart redeems a share of preferred shares held by the preferred shares depositary, the preferred shares depositary will redeem as of the same redemption date a proportionate number of depositary shares representing the shares of preferred shares that were redeemed. The redemption price per depositary share will be equal to the aggregate redemption price payable with respect to the number of shares of preferred shares underlying the depositary shares. If fewer than all the depositary shares are to be redeemed, the depositary shares to be redeemed will be selected by lot or proportionately as CubeSmart may determine.

        After the date fixed for redemption, the depositary shares called for redemption will no longer be deemed to be outstanding and all rights of the holders of the depositary shares will cease, except the right to receive the redemption price. Any funds that we deposit with the preferred shares depositary relating to depositary shares which are not redeemed by the holders of the depositary shares will be returned to us after a period of two years from the date the funds are deposited by CubeSmart.

Voting

        Upon receipt of notice of any meeting at which the holders of any shares of preferred shares underlying the depositary shares are entitled to vote, the preferred shares depositary will mail the information contained in the notice to the record holders of the depositary receipts. Each record holder of the depositary receipts on the record date, which will be the same date as the record date for the preferred shares, may then instruct the preferred shares depositary as to the exercise of the voting rights pertaining to the number of shares of preferred shares underlying that holder's depositary shares. The preferred shares depositary will try to vote the number of shares of preferred shares underlying the depositary shares in accordance with the instructions, and we will agree to take all reasonable action which the preferred shares depositary deems necessary to enable the preferred shares depositary to do so. The preferred shares depositary will abstain from voting the preferred shares to the extent that it does not receive specific written instructions from holders of depositary receipts representing the preferred shares.

Record Date

        Subject to the provisions of the deposit agreement, whenever

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Withdrawal of Preferred Shares

        Upon surrender of depositary receipts at the principal office of the preferred shares depositary, upon payment of any unpaid amount due the preferred shares depositary, and subject to the terms of the deposit agreement, the owner of the depositary shares evidenced by the depositary receipts is entitled to delivery of the number of whole shares of preferred shares and all money and other property, if any, represented by the depositary shares. Partial shares of preferred shares will not be issued. If the depositary receipts delivered by the holder evidence a number of depositary shares in excess of the number of depositary shares representing the number of whole shares of preferred shares to be withdrawn, the preferred shares depositary will deliver to the holder at the same time a new depositary receipt evidencing the excess number of depositary shares. Holders of preferred shares that are withdrawn will not be entitled to deposit the shares that have been withdrawn under the deposit agreement or to receive depositary receipts.

Amendment and Termination of the Deposit Agreement

        CubeSmart and the preferred shares depositary may at any time agree to amend the form of depositary receipt and any provision of the deposit agreement. However, any amendment that materially and adversely alters the rights of holders of depositary shares will not be effective unless the amendment has been approved by the holders of at least a majority of the depositary shares then outstanding. The deposit agreement may be terminated by CubeSmart or by the preferred shares depositary only if all outstanding shares have been redeemed or if a final distribution in respect of the underlying preferred shares has been made to the holders of the depositary shares in connection with our liquidation, dissolution or winding up.

Charges of Preferred Shares Depositary

        CubeSmart will pay all charges of the preferred shares depositary including charges in connection with the initial deposit of the preferred shares, the initial issuance of the depositary receipts, the distribution of information to the holders of depositary receipts with respect to matters on which preference shares is entitled to vote, withdrawals of the preferred shares by the holders of depositary receipts or redemption or conversion of the preferred shares, except for taxes (including transfer taxes, if any) and other governmental charges and any other charges expressly provided in the deposit agreement to be at the expense of holders of depositary receipts or persons depositing preferred shares.

Miscellaneous

        Neither CubeSmart nor the preferred shares depositary will be liable if either of us is prevented or delayed by law or any circumstance beyond our control in performing any obligations under the deposit agreement. The obligations of the preferred shares depositary under the deposit agreement are limited to performing its duties under the agreement without negligence or bad faith. Our obligations under the deposit agreement are limited to performing our duties in good faith. Neither CubeSmart nor the preferred shares depositary is obligated to prosecute or defend any legal proceeding in respect of any depositary shares or preferred shares unless satisfactory indemnity is furnished. CubeSmart and the preferred shares depositary may rely on advice of or information from counsel, accountants or other persons that they believe to be competent and on documents that they believe to be genuine.

        The preferred shares depositary may resign at any time or be removed by CubeSmart, effective upon the acceptance by its successor of its appointment. If CubeSmart has not appointed a successor preferred shares depositary and the successor depositary has not accepted its appointment within 60 days after the preferred shares depositary delivered a resignation notice to CubeSmart, the preferred shares depositary may terminate the deposit agreement. See "—Amendment and Termination of the Deposit Agreement" above.

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DESCRIPTION OF SUBSCRIPTION RIGHTS

        CubeSmart may issue subscription rights to purchase common shares, preferred shares, or depositary shares. CubeSmart may issue subscription rights independently or together with any other offered security, which may or may not be transferable by the shareholder. In connection with any offering of subscription rights, CubeSmart may enter into a standby arrangement with one or more underwriters or other purchasers pursuant to which the underwriters or other purchasers may be required to purchase any securities remaining unsubscribed for after such offering.

        The prospectus supplement relating to any subscription rights CubeSmart may offer will contain the specific terms of the subscription rights. These terms may include the following:

        The description in the applicable prospectus supplement of any subscription rights CubeSmart offers will not necessarily be complete and will be qualified in its entirety by reference to the applicable subscription rights certificate or subscription rights agreement, which will be filed with the SEC if CubeSmart offers subscription rights. For more information on how you can obtain copies of any subscription rights certificate or subscription rights agreement if CubeSmart offers subscription rights, see "Where You Can Find More Information." CubeSmart urges you to read the applicable subscription rights certificate, the applicable subscription rights agreement and any applicable prospectus supplement in their entirety.

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DESCRIPTION OF WARRANTS

        CubeSmart may issue warrants for the purchase of common shares, preferred shares or depositary shares. CubeSmart may issue warrants independently or together with any offered securities. The warrants may be attached to or separate from those offered securities. CubeSmart will issue the warrants under one or more warrant agreements to be entered into between CubeSmart and a warrant agent to be named in the applicable prospectus supplement. The warrant agent will act solely as our agent in connection with the warrants and will not assume any obligation or relationship of agency or trust for or with any holders or beneficial owners of warrants.

        The prospectus supplement relating to any warrants that CubeSmart may offer will contain the specific terms of the warrants. These terms may include the following:

Exercise of Warrants

        Each warrant will entitle the holder of the warrant to purchase for cash the amount of CubeSmart's common shares, preferred shares and/or depositary shares, as the case may be, at the exercise price stated or determinable in the applicable prospectus supplement for the warrants. Warrants may be exercised at any time up to the close of business on the expiration date shown in the applicable prospectus supplement, unless otherwise specified in such prospectus supplement. After the close of business on the expiration date, unexercised warrants will become void. Warrants may be exercised as described in the applicable prospectus supplement. When the warrant holder makes the payment and properly completes and signs the warrant certificate at the corporate trust office of the warrant agent or any other office indicated in the prospectus supplement, CubeSmart will, as soon as possible, forward the common shares, preferred shares and/or depositary shares that the warrant holder has purchased, as the case may be. If the warrant holder exercises the warrant for less than all of the

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warrants represented by the warrant certificate, CubeSmart will issue a new warrant certificate for the remaining warrants.

        The description in the applicable prospectus supplement of any warrants CubeSmart offers will not necessarily be complete and will be qualified in its entirety by reference to the applicable warrant agreement and warrant certificate, which will be filed with the SEC if CubeSmart offers warrants. For more information on how you can obtain copies of any warrant certificate or warrant agreement if we offer warrants, see "Where You Can Find More Information." We urge you to read the applicable warrant certificate, the applicable warrant agreement and any applicable prospectus supplement in their entirety.

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DESCRIPTION OF THE DEBT SECURITIES

        The following summary sets forth the general terms and provisions of the indenture under which the debt securities will be issued by the Operating Partnership. The debt securities will be issued by the Operating Partnership under an indenture, as amended or supplemented from time to time, among the Operating Partnership, CubeSmart, as guarantor, and U.S. Bank National Association, as trustee.

        The debt securities may be issued from time to time in one or more series. The particular terms and provisions of the debt securities with respect to a specific offering of debt securities will be set forth in the applicable prospectus supplement. This summary of general terms and provisions of the indenture and the debt securities does not purport to be complete and is subject to, and is qualified in its entirety by reference to, all provisions of the indenture and those debt securities.

        The indenture is filed as an exhibit to the registration statement of which this prospectus is a part and will be available for inspection at the corporate trust office of the trustee or as described under "Where You Can Find More Information." The indenture will be qualified under, subject to, and governed by, the Trust Indenture Act of 1939, as amended, or the Trust Indenture Act.

        All section references appearing herein are to sections of the indenture, and capitalized terms used but not defined herein will have the respective meanings set forth in the indenture.

General

        The debt securities will be direct, unsecured obligations of the Operating Partnership. Except for any series of debt securities which is expressly subordinated to other indebtedness of the Operating Partnership, the debt securities will rank equally with all other unsecured and unsubordinated indebtedness of the Operating Partnership. Under the indenture, the debt securities may be issued without limit as to aggregate principal amount, in one or more series, as established from time to time pursuant to authority granted by a resolution of the board of trustees of CubeSmart as sole general partner of the Operating Partnership or as established in one or more supplemental indentures to the indenture. All of the debt securities of any one series need not be issued at the same time and, unless otherwise provided, a series may be reopened, without the consent of the holders of the debt securities of that series, for issuances of additional debt securities of that series. All debt securities of a particular series shall be substantially identical except as to denomination, date of issuance, issue price and the date from which interest, if any, shall accrue.

        All of the debt securities will be fully and unconditionally guaranteed as to payment of principal and premium, if any, and interest by CubeSmart. The indenture allows certain of our subsidiaries from time to time to become guarantors of specific series of the debt securities.

        The indenture provides that there may be more than one trustee for any one or more series of debt securities. Any trustee under the indenture may resign or be removed with respect to one or more series of debt securities, and a successor trustee may be appointed to act with respect to that series. Except as otherwise indicated in this prospectus or the applicable prospectus supplement, any action to be taken by the trustee may be taken by each such trustee with respect to, and only with respect to, the one or more series of debt securities for which it is trustee under the indenture.

Terms

        The applicable prospectus supplement relating to the series of debt securities being offered will describe the specific terms and provisions of those debt securities, including the following:

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        The debt securities may provide for less than the entire principal amount of those debt securities to be payable upon declaration of acceleration of the maturity thereof ("original issue discount securities"). The applicable prospectus supplement will describe special U.S. federal income tax, accounting and other considerations applicable to the original issue discount securities.

        The indenture does not contain any provisions that would limit the ability of the Operating Partnership to incur indebtedness or that would afford holders of debt securities protection in the event of a highly leveraged or similar transaction involving the Operating Partnership. However, restrictions on ownership and transfers of CubeSmart's common shares and preferred shares, designed to preserve CubeSmart's status as a REIT, may prevent or hinder a change of control. Reference is made to the applicable prospectus supplement for information with respect to any deletions from, modifications of or additions to the events of default or covenants of the Operating Partnership that are described below, including any addition of a covenant or other provision providing event risk or similar protection.

Guarantee

        CubeSmart will, under the indenture, fully and unconditionally guarantee the due and punctual payment of principal of and premium, if any, and interest on all debt securities issued by the Operating Partnership, and the due and punctual payment of any sinking fund payments on those debt securities, when and as the same will become due and payable, whether at a maturity date, by declaration of acceleration, call for redemption or otherwise.

        From time to time, subsidiaries of the Operating Partnership may join as guarantors under the indenture. Such subsidiaries' guarantees will be limited to the series of debt securities for which they execute notations of guarantee in accordance with the terms of the indenture, and may be released in connection with:

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        The obligations of each guarantor, other than CubeSmart, under its guarantee will be limited as necessary to prevent that guarantee from constituting a fraudulent conveyance or fraudulent transfer under applicable law.

Denominations

        Unless otherwise specified in the applicable prospectus supplement, the debt securities of any series shall be issuable only in registered form without coupons and, other than securities in global form (which may be of any denomination), will be issuable in denominations of $2,000 and integral multiples of $1,000 in excess thereof.

Payments

        Unless otherwise specified in the applicable prospectus supplement, the principal of and premium, if any, and interest on any series of debt securities will be payable at the corporate trust office of the trustee. However, at the option of the Operating Partnership, payment of interest may be made by check mailed to the address of the person entitled thereto as it appears in the security register or by wire transfer of funds to that person at a bank account maintained within the United States.

        All amounts paid by the Operating Partnership to a paying agent or a trustee for the payment of the principal of or premium, if any, or interest on any debt security which remains unclaimed at the end of two years after the principal, premium or interest has become due and payable will be repaid to the Operating Partnership, and the holder of the debt security thereafter may look only to the Operating Partnership for payment of these amounts.

        Any interest not punctually paid or duly provided for on any interest payment date with respect to a debt security will forthwith cease to be payable to the holder on the applicable regular record date and may either be paid to the person in whose name that debt security is registered at the close of business on a special record date for the payment of that defaulted interest to be fixed by the trustee or may be paid at any time in any other lawful manner, all in accordance with the indenture. Notice of any special record date will be given to the holder of that debt security not less than 10 days prior to the special record date.

Registration and Transfer

        Subject to certain limitations imposed upon debt securities issued in book-entry form, the debt securities of any series will be exchangeable for other debt securities of the same series, of a like aggregate principal amount and tenor, of different authorized denominations upon surrender of such debt securities at the corporate trust office of the trustee. In addition, subject to certain limitations imposed upon debt securities issued in book-entry form, the debt securities of any series may be surrendered for registration of transfer at the corporate trust office of the trustee.

        Every debt security surrendered for registration of transfer or exchange will be duly endorsed or accompanied by a written instrument of transfer. No service charge will be made for any registration of transfer or exchange of any debt securities, but the Operating Partnership may require payment of a sum sufficient to cover any tax or other governmental charge payable in connection therewith.

        If the applicable prospectus supplement refers to any transfer agent (in addition to the trustee) initially designated by the Operating Partnership and the guarantors with respect to any series of debt securities, the Operating Partnership may at any time rescind the designation of that transfer agent or approve a change in the location through which that transfer agent acts, except that the Operating Partnership and the guarantors will be required to maintain a transfer agent in each place of payment for that series. The Operating Partnership and the guarantors may at any time designate additional transfer agents with respect to any series of debt securities.

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        Neither the Operating Partnership nor the trustee will be required to:

Merger, Consolidation and Sale

        Unless otherwise provided in the applicable prospectus supplement, the Operating Partnership may consolidate with, or sell, lease or convey all or substantially all of its assets to, or merge with or into, any other entity, provided that the following conditions are satisfied or fulfilled:

        Unless otherwise provided in the applicable prospectus supplement, CubeSmart may consolidate with, or sell, lease or convey all or substantially all its assets to, or merge with or into, any other entity, provided that substantially the same conditions as above are satisfied or fulfilled.

Covenants

        We will set forth in the applicable prospectus supplement any financial covenants applicable to any issue of debt securities.

        Unless otherwise provided in the applicable prospectus supplement, so long as any debt securities are outstanding, CubeSmart and the Operating Partnership will furnish to the trustee such information, documents and other reports as may be required by the Trust Indenture Act, including filing with the trustee within 15 days information, documents or reports required to be filed by the Issuer with the SEC.

        The Operating Partnership and the guarantors may choose not to comply with any term, provision or condition of certain covenants if at any time the holders of at least a majority in principal amount of all the outstanding debt securities, by act of those holders, either waive compliance in that instance or generally waive compliance with that covenant. Except to the extent so expressly waived, and until any waiver becomes effective, the Operating Partnership's and the guarantors' obligations and the duties of the trustee in respect of any such term, provision or condition will remain in full force and effect.

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        Unless otherwise provided in the applicable prospectus supplement, except as permitted under "Merger, Consolidation or Sale," each of the Operating Partnership and the guarantors will do or cause to be done all things necessary to preserve and keep in full force and effect its existence, rights (declaration and statutory) and franchises; provided, however, that neither the Operating Partnership nor any guarantor will be required to preserve any right or franchise if the board of directors of the Operating Partnership, or the board of trustees or analogous body of any subsidiary guarantor, determines that the preservation thereof is no longer necessary or desirable in the conduct of its business and that the loss of that right or franchise is not disadvantageous in any material respect to the holders of the debt securities.

        Unless otherwise provided in the applicable prospectus supplement, each of the Operating Partnership and the guarantors will cause all of its material properties used or useful in the conduct of its business or the business of any of its Subsidiaries to be maintained and kept in good condition, repair and working order, all as in the judgment of the Operating Partnership or the applicable guarantor may be necessary so that the business carried on in connection with those properties may be properly and advantageously conducted at all times; provided, however, that, subject to the covenant described under "Merger, Consolidation and Sale" above, neither the Operating Partnership nor any guarantor nor any of their respective Subsidiaries will be prevented from selling or otherwise disposing of their properties at any time.

        Unless otherwise provided in the applicable prospectus supplement, each of the Operating Partnership and the guarantors will pay or discharge or cause to be paid or discharged, before becoming delinquent:

provided, however, that neither the Operating Partnership nor any guarantor will be required to pay or discharge or cause to be paid or discharged any tax, assessment, charge or claim whose amount or applicability is being contested in good faith.

        Unless otherwise provided in the applicable prospectus supplement, each of the Operating Partnership and the guarantors will pay to any holder of debt securities that is a United States Alien such additional amounts as may be required such that every net payment on the debt securities held by such holder, after deduction or withholding on account of any present or future U.S. tax (other than taxes unrelated to the holder's ownership of the debt securities and certain other taxes), is not less than the amount provided in such debt securities as then due and payable.

        The applicable prospectus supplement relating to the series of debt securities being offered will describe any additional covenants specific to that series.

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Events of Default, Notice and Waiver

        Unless otherwise provided in the applicable prospectus supplement, the indenture provides that the following events will be "events of default" with respect to any series of debt securities issued under the indenture:

        Unless otherwise provided in the applicable prospectus supplement, if an event of default (other than as described in clause (6) above) with respect to debt securities of any series at the time outstanding occurs and is continuing, then in each case the trustee or the holders of not less than 25% in principal amount of the outstanding debt securities of that series may declare the principal (or, if the debt securities of that series are original issue discount securities or indexed securities, that portion of the principal amount as may be specified in the terms thereof) of and premium, if any, and accrued and unpaid interest on all of the debt securities of that series to be due and payable immediately by written notice thereof to the Operating Partnership and CubeSmart (and to the trustee if given by the holders). If an event of default described in clause (6) above occurs and is continuing, the principal (or such portion thereof) of and premium, if any, and accrued and unpaid interest on all of the debt securities of that series will become and be immediately due and payable without any declaration or other act on the part of the trustee or any holders. However, at any time after any acceleration with respect to debt securities of that series, but before a judgment or decree for payment of the amounts due has been obtained by the trustee, the holders of not less then a majority in principal amount of outstanding debt securities of that series may rescind and annul that acceleration and its consequences if (1) the Operating Partnership or any guarantor has paid or deposited with the trustee all required payments of the principal of and premium, if any, and interest on the debt securities of that series

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(without giving effect to the acceleration) plus certain fees, expenses, disbursements and, premium, if any, advances of the trustee and (2) all events of default, other than the nonpayment of accelerated principal, premium, if any, or interest with respect to debt securities of that series, have been cured or waived as provided in the indenture. The indenture also provides that the holders of not less than a majority in principal amount of the outstanding debt securities of any series may waive any past default with respect to that series and its consequences, except a default (A) in the payment of the principal of or premium, if any, or interest on any debt security of that series or (B) in respect of a covenant or provision contained in the indenture that cannot be modified or amended without the consent of the holder of each outstanding debt security affected thereby.

        The trustee will be required to give notice to the holders of debt securities within 90 days of a default under the indenture unless such default has been cured or waived; provided, however, that the trustee may withhold notice to the holders of any series of debt securities of any default with respect to that series (except a default in the payment of the principal of or premium, if any, or interest on any debt securities of that series or in the payment of any sinking fund installment in respect of any debt securities of that series) if the responsible officers of the trustee consider withholding of notice to be in the interest of the holders.

        The indenture provides that no holders of debt securities of any series may institute any judicial or other proceedings with respect to the indenture or for any remedy thereunder, except in the case of failure of the trustee, for 60 days, to act after it has received a written request to institute proceedings in respect of an event of default from the holders of not less than 25% in principal amount of the outstanding debt securities of that series, as well as an offer of reasonable security or indemnity. This provision will not prevent, however, any holder of debt securities from instituting suit for the enforcement of payment of the principal of and premium, if any, and interest on the debt securities at the respective due date or dates for payment.

        Subject to provisions in the indenture relating to its duties in case of default, the trustee is under no obligation to exercise any of its rights or powers under the indenture at the request or direction of any holders of debt securities of any series then outstanding under the indenture, unless the holders offer to the trustee reasonable security or indemnity. The holders of not less than a majority in principal amount of the outstanding debt securities of any series will have the right to direct the time, method and place of conducting any proceeding for any remedy available to the trustee, or of exercising any trust or power conferred upon the trustee for that series. However, the trustee may refuse to follow any direction which is in conflict with any law or the indenture, which may involve the trustee in personal liability or which may be unduly prejudicial to the holders of debt securities of that series not joining in the proceeding.

        Within 120 days after the end of each fiscal year, the Operating Partnership and CubeSmart must deliver to the trustee a certificate, signed by one of several specified officers of the general partner of the Operating Partnership and of CubeSmart, stating whether or not such officers have knowledge of any default under the indenture and, if so, specifying each such default and the nature and status thereof.

Modification of the Indenture

        Modifications and amendments of provisions of the indenture applicable to any series may be made only with consent of the holders of more than 50% in principal amount of all outstanding debt securities which are affected by the modification or amendment; provided, however, that no such modification or amendment may, without the consent of the holder of each debt security affected thereby:

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        Modifications and amendments of the indenture may be made by the Operating Partnership, the guarantors and the trustee without the consent of any holder of debt securities for any of the following purposes:

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        The indenture provides that, in determining whether the holders of the requisite principal amount of outstanding debt securities of a series have given any request, demand, authorization, direction, notice, consent or waiver thereunder or whether a quorum is present at a meeting of holders of debt securities:

        The indenture contains provisions for convening meetings of the holders of debt securities of a series. A meeting may be called at any time by the trustee, and also, upon request, by the Operating Partnership or the holders of at least 25% in principal amount of the outstanding debt securities of that series, in each case upon notice given as provided in the indenture. Except for any consent that must be given by the holder of each debt security affected by certain modifications and amendments of the indenture, any resolution presented at a meeting or adjourned meeting duly reconvened at which a quorum is present may be adopted by the affirmative vote of the holders of a majority in principal amount of the outstanding debt securities of that series; provided, however, that, except as referred to above, any resolution with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that may be made, given or taken by the holders of a specified percentage,

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which is less than a majority, in principal amount of the outstanding debt securities of a series may be adopted at a meeting or adjourned meeting duly reconvened at which a quorum is present by the affirmative vote of the holders of the debt securities of that series. Any resolution passed or decision taken at any meeting of holders of debt securities of any series duly held in accordance with the indenture will be binding on all holders of debt securities of that series. The quorum at any meeting called to adopt a resolution, and at any reconvened meeting, will be persons holding or representing a majority in principal amount of the outstanding debt securities of a series; provided, however, that if any action is to be taken at such meeting with respect to a consent or waiver which may be given by the holders of not less than a specified percentage in principal amount of the outstanding debt securities of a series, the persons holding or representing such specified percentage in principal amount of the outstanding debt securities of such series will constitute a quorum.

        Notwithstanding the foregoing provisions, if any action is to be taken at a meeting of holders of debt securities of any series with respect to any request, demand, authorization, direction, notice, consent, waiver or other action that the indenture expressly provides may be made, given or taken by the holders of a specified percentage in principal amount of all outstanding debt securities affected thereby, or of the holders of that series and one or more additional series:

Discharge; Legal Defeasance and Covenant Defeasance

        Unless otherwise provided in the applicable prospectus supplement, the Operating Partnership and the guarantors may discharge certain obligations to holders of any series of debt securities that have not already been delivered to the trustee for cancellation and that either have become due and payable or will become due and payable within one year (or are scheduled for redemption within one year) by irrevocably depositing with the trustee, in trust, funds in such currency or currencies, currency unit or units or composite currency or currencies in which such debt securities are payable in an amount sufficient to pay the entire indebtedness on such debt securities in respect of principal and premium, if any, and interest to the date of such deposit (if such debt securities have become due and payable) or to the stated maturity or redemption date, as the case may be.

        In addition, the indenture provides that, unless otherwise provided in the applicable prospectus supplement, the Operating Partnership may elect either:

in either case upon the irrevocable deposit by the Operating Partnership or the guarantors with the trustee, in trust, of any amount, in such currency or currencies, currency unit or units or composite

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currency or currencies in which those debt securities are payable at stated maturity, or Government Obligations, or both, applicable to those debt securities which through the scheduled payment of principal and interest in accordance with their terms will provide money in an amount sufficient, based on a certification by officers of the Operating Partnership, to pay the principal of and premium, if any, and interest on such debt securities, and any mandatory sinking fund or analogous payments thereon, on the scheduled due dates.

        This trust may only be established if, among other conditions, the Operating Partnership has delivered to the trustee an opinion of counsel to the effect that the holders of the debt securities will not recognize income, gain or loss for U.S. federal income tax purposes as a result of legal defeasance or covenant defeasance, as the case may be, and will be subject to U.S. federal income tax on the same amounts, in the same manner and at the same times as would have been the case if legal defeasance or covenant defeasance, as the case may be, had not occurred, and the opinion of counsel, in the case of legal defeasance, must refer to and be based upon a ruling of the Internal Revenue Service or a change in applicable U.S. federal income tax law occurring after the date of the indenture.

        In the event the Operating Partnership effects covenant defeasance with respect to the debt securities of any series and those debt securities are declared due and payable because of the occurrence of any event of default other than an event of default described in clause (4) under "Events of Default, Notice and Waiver" with respect to the covenants described under "—Covenants" (which would no longer be applicable to those debt securities) or described in clause (7) under "Events of Default, Notice and Waiver" with respect to any other covenant as to which there has been covenant defeasance, the amount in the currency, currency unit or composite currency in which those debt securities are payable, and Government Obligations on deposit with the trustee, will be sufficient to pay amounts due on those debt securities at the time of their stated maturity but may not be sufficient to pay amounts due on those debt securities at the time of the acceleration resulting from such event of default. However, the Operating Partnership and the guarantors would remain liable to make payment of those amounts due at the time of acceleration.

        The applicable prospectus supplement may further describe the provisions, if any, permitting legal defeasance or covenant defeasance, including any modifications to the provisions described above, with respect to the debt securities of a particular series.

Subordination

        The terms and conditions, if any, upon which the debt securities of any series will be subordinated to other indebtedness of the Operating Partnership, including the debt securities of other series, will be set forth in the applicable prospectus supplement. These terms will include a description of the indebtedness ranking senior to the debt securities of that series, the restrictions on payments to the holders of the debt securities of that series while a default with respect to the senior indebtedness is continuing, the restrictions, if any, on payments to the holders of the debt securities of that series following an event of default, and provisions requiring holders of the debt securities of that series to remit certain payments to holders of senior indebtedness.

Book-Entry System and Global Securities

        The debt securities of a series may be issued in whole or in part in the form of one or more securities in global form that will be deposited with, or on behalf of, a depository identified in the applicable prospectus supplement relating to that series. Global securities, if any, issued in the United States are expected to be deposited with The Depository Trust Company, or "DTC," as depository. Unless otherwise indicated, global securities will be issued in fully registered form and in either temporary or permanent form. Unless the applicable prospectus supplement states otherwise, and until it is exchanged in whole or in part for the debt securities represented thereby, a global security may not

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be transferred except as a whole by the depository for that global security to a nominee of that depository or by a nominee of that depository to that depository or another nominee of such depository or by that depository or any nominee of that depository to a successor depository or any nominee of that successor.

        The specific terms of the depository arrangement with respect to a series of debt securities will be described in the applicable prospectus supplement. We anticipate that, unless otherwise indicated in the applicable prospectus supplement, the following provisions will apply to depository arrangements.

        The applicable prospectus supplement will state whether the global securities will be issued in certificated or book-entry form. If the global securities are to be issued in book-entry form, we expect that upon the issuance of a global security, the depository for the global security or its nominee will credit on its book-entry registration and transfer system the respective principal amounts of the individual debt securities represented by the global security to the accounts of persons that have accounts with such depository ("participants"). These accounts will be designated by the underwriters, dealers or agents with respect to the debt securities. Ownership of beneficial interests in a global security will be limited to participants or persons that may hold interests through participants.

        We expect that, for the global securities deposited with DTC, pursuant to procedures established by DTC, ownership of beneficial interests in any global security with respect to which DTC is the depository will be shown on, and the transfer of that ownership will be effected only through, records maintained by DTC or its nominee (with respect to beneficial interests of participants) and records of participants (with respect to beneficial interests of persons who hold through participants). None of the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar will have any responsibility or liability for any aspect of the records of DTC or for maintaining, supervising or reviewing any records of DTC or any of its participants relating to beneficial ownership interests in the debt securities. The laws of some states require that certain purchasers of securities take physical delivery of such securities in definitive form. These limits and laws may impair the ability to own, pledge or transfer beneficial interest in a global security.

        Unless otherwise specified in the applicable prospectus supplement or the actual global security, so long as the depository for a global security or its nominee is the registered owner of the book-entry global security, the depository or that nominee, as the case may be, will be considered the sole owner or holder of the debt securities represented by that global security for all purposes under the applicable indenture. Except as described below or in the applicable prospectus supplement or the global security, owners of beneficial interest in a global security will not be entitled to have any of the individual debt securities represented by the global security registered in their names, will not receive or be entitled to receive delivery of debt securities in definitive certificated form and will not be considered the owners or holders thereof under the applicable indenture. Beneficial owners of debt securities evidenced by a global security will not be considered the owners or holders thereof under the indenture for any purpose, including with respect to the giving of any direction, instructions or approvals to the trustee thereunder. Accordingly, each person owning a beneficial interest in a global security with respect to which DTC is the depository must rely on the procedures of DTC and, if that person is not a participant, on the procedures of the participant through which that person owns its interests, to exercise any rights of a holder under the applicable indenture. We understand that, under existing industry practice, if we request any action of holders or if an owner of a beneficial interest in a global security desires to give or take any action which a holder is entitled to give or take under the applicable indenture, DTC would authorize the participants holding the relevant beneficial interest to give or take that action, and the participants would authorize beneficial owners through the participants to give or take that action or would otherwise act upon the instructions of beneficial owners holding through them.

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        Payments of principal of and premium, if any, and interest on debt securities represented by a global security registered in the name of a depository or its nominee will be made to or at the direction of the depository or its nominee, as the case may be, as the registered owner of the global security under the indenture. Under the terms of the indenture, the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar may treat the persons in whose name debt securities, including a global security, are registered as the owners thereof for the purpose of receiving such payments. Consequently, none of the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar has or will have any responsibility or liability for the payment of those amounts to beneficial owners of debt securities (including principal, premium, if any, and interest). We believe, however, that it is currently the policy of DTC to immediately credit the accounts of relevant participants with payments, in amounts proportionate to their respective holdings of beneficial interests in the relevant global security as shown on the records of DTC or its nominee. Payments by participants to owners of beneficial interests in the global security held through participants will be governed by standing instructions and customary practices, as is the case with securities held for the account of customers in bearer form or registered in street name, and will be the responsibility of the participants. Redemption notices with respect to any debt securities represented by a global security will be sent to the depository or its nominee. If less than all of the debt securities of any series are to be redeemed, we expect the depository to determine the amount of the interest of each participant in the debt securities to be redeemed to be determined by lot. None of the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar for the debt securities will have any responsibility or liability for any aspect of the records relating to or payments made on account of beneficial ownership interests in the global security for the debt securities or for maintaining any records with respect thereto.

        None of the Operating Partnership, the guarantors, the trustee, any paying agent and the security registrar will be liable for any delay by the holders of a global security or the depository in identifying the beneficial owners of debt securities and the Operating Partnership, the guarantors and the trustee may conclusively rely on, and will be protected in relying on, instructions from the holder of a global security or the depository for all purposes. The rules applicable to DTC and its participants are on file with the SEC.

        If a depository for any debt securities is at any time unwilling, unable or ineligible to continue as depository and a successor depository is not appointed by the Operating Partnership within 90 days, the Operating Partnership will issue definitive certificated debt securities in exchange for the global security representing those debt securities. If an event of default has occurred and is continuing with respect to the debt securities of any series, the Operating Partnership will issue definitive certificated debt securities in exchange for the global security or securities representing the debt securities of such series. In addition, the Operating Partnership may at any time and in its sole discretion, subject to any limitations described in the applicable prospectus supplement or the global security relating to the debt securities, determine not to have any of the debt securities represented by one or more global securities and in such event will issue definitive certificated debt securities in exchange for the global security or securities representing the debt securities.

        The debt securities of a series may also be issued in whole or in part in the form of one or more bearer global securities that will be deposited outside of the United States with a depository, or with a nominee for the depository, identified in the applicable prospectus supplement and/or global security. Any such bearer global securities may be issued in temporary or permanent form. The specific terms and procedures, including the specific terms of the depository arrangement, with respect to any portion of a series of debt securities to be represented by one or more bearer global securities will be described in the applicable prospectus supplement and/or global security.

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Certain Definitions

        The following are certain defined terms used in this prospectus and the indenture. We refer you to the indenture for the complete definition of all defined terms, as well as any other capitalized terms used in this prospectus or the applicable prospectus supplement for which no definition is provided (Section 101).

        For purposes of the following definitions and the indenture generally, all calculations and determinations will be made in accordance with generally accepted accounting principles and will be based upon the consolidated financial statements of the Operating Partnership and its Subsidiaries prepared in accordance with generally accepted accounting principles.

        "Government Obligations" means securities which are:

        "Subsidiary" means, as to any person, (a) any corporation more than 50% of whose stock of any class or classes having by the terms thereof ordinary voting power to elect a majority of the directors of such corporation (irrespective of whether or not at the time, any class or classes of stock of such corporation shall have or might have voting power by reason of the lapse of time or the happening of any contingency) is at the time owned by such person directly or indirectly through Subsidiaries, and (b) any partnership, association, joint venture, limited liability company, trust or other entity in which such person directly or indirectly through Subsidiaries has more than a 50% equity interest or 50% Capital Percentage at any time. For the purpose of this definition, "Capital Percentage" means, with respect to the interest of CubeSmart, the Operating Partnership or one of its Subsidiaries in any partnership, association, joint venture, limited liability company, trust or other entity, the percentage interest of such partnership, association, joint venture, limited liability company, trust or other entity based on the aggregate amount of net capital contributed by CubeSmart, the Operating Partnership or such Subsidiary in such partnership, association, joint venture, limited liability company, trust or other entity at the time of determination relative to all capital contributions made in such partnership, association, joint venture, limited liability company, trust or other entity at such time of determination.

        "United States Alien" means any corporation, partnership, individual or fiduciary that is, as to the United States, a foreign corporation, a nonresident alien individual, a nonresident fiduciary of a foreign estate or trust, or a foreign partnership one or more of the members of which is, as to the United States, a foreign corporation, a nonresident alien individual or a nonresident fiduciary of a foreign estate or trust.

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MATERIAL FEDERAL INCOME TAX CONSIDERATIONS

        The following discussion describes the material U.S. federal income tax considerations relating to the purchase, ownership and disposition of common shares and preferred shares of CubeSmart and debt securities of the Operating Partnership, and the qualification and taxation of CubeSmart as a REIT under the Internal Revenue Code of 1986, as amended (the "Code").

        This discussion is not exhaustive of all possible tax considerations and does not provide a detailed discussion of any state, local or foreign tax considerations. The discussion does not address all aspects of taxation that may be relevant to particular investors in light of their personal investment or tax circumstances, or to certain types of investors that are subject to special treatment under the federal income tax laws, such as insurance companies, regulated investment companies, REITs, tax-exempt organizations (except to the limited extent discussed below under "Taxation of Tax-Exempt Shareholders"), financial institutions or broker-dealers, non-U.S. individuals and foreign corporations (except to the limited extent discussed below under "Taxation of Non-U.S. Shareholders") and other persons subject to special tax rules. This summary deals only with investors who hold common shares or preferred shares of CubeSmart or debt securities of the Operating Partnership as "capital assets" within the meaning of Section 1221 of the Code. This discussion is not intended to be, and should not be construed as, tax advice.

        The information in this summary is based on the Code, current, temporary and proposed Treasury regulations, the legislative history of the Code, current administrative interpretations and practices of the Internal Revenue Service (the "IRS"), including its practices and policies as endorsed in private letter rulings, which are not binding on the IRS, and existing court decisions. Future legislation, regulations, administrative interpretations and court decisions could change current law or adversely affect existing interpretations of current law. Any change could apply retroactively. We have not obtained any rulings from the IRS concerning the tax treatment of the matters discussed in this summary. Therefore, it is possible that the IRS could challenge the statements in this summary, which do not bind the IRS or the courts, and that a court could agree with the IRS.

        We urge you to consult your tax advisor regarding the specific tax consequences to you of ownership of common shares or preferred shares of CubeSmart and debt securities of the Operating Partnership, and of CubeSmart's election to be taxed as a REIT. Specifically, you should consult your tax advisor regarding the federal, state, local, foreign, and other tax consequences of such ownership and election, and regarding potential changes in applicable tax laws.

Taxation of CubeSmart

        CubeSmart elected to be taxed as a REIT under the federal income tax laws beginning with its short taxable year ended December 31, 2004. CubeSmart believes that, beginning with such short taxable year, it has been organized and has operated in such a manner as to qualify for taxation as a REIT under the Code and intends to continue to operate in such a manner. However, there can be no assurance that CubeSmart has qualified or will remain qualified as a REIT.

        CubeSmart's continued qualification and taxation as a REIT depend upon its ability to meet on a continuing basis, through actual annual operating results, certain qualification tests set forth in the federal income tax laws. Those qualification tests involve the percentage of income that CubeSmart earns from specified sources, the percentage of its assets that falls within specified categories, the diversity of its share ownership, and the percentage of its earnings that CubeSmart distributes. Accordingly, no assurance can be given that the actual results of CubeSmart's operations for any particular taxable year will satisfy such requirements. For a discussion of the tax consequences of its failure to qualify as a REIT, see "Requirements for Qualification—Failure to Qualify" below.

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        Pursuant to CubeSmart's declaration of trust, CubeSmart's board of trustees has the authority to make any tax elections on its behalf that, in its sole judgment, are in CubeSmart's best interest. This authority includes the ability to revoke or otherwise terminate CubeSmart's status as a REIT. CubeSmart's board of trustees has the authority under its declaration of trust to make these elections without the necessity of obtaining the approval of CubeSmart's shareholders. In addition, CubeSmart's board of trustees has the authority to waive any restrictions and limitations contained in its declaration of trust that are intended to preserve CubeSmart's status as a REIT during any period in which its board of trustees has determined not to pursue or preserve CubeSmart's status as a REIT.

        The sections of the Code relating to qualification and operation as a REIT, and the federal income taxation of a REIT, are highly technical and complex. The following discussion sets forth only the material aspects of those sections. This summary is qualified in its entirety by the applicable Code provisions and the related rules and regulations.

        If CubeSmart qualifies as a REIT, it generally will not be subject to federal income tax on the taxable income that it distributes to its shareholders. The benefit of that tax treatment is that it avoids the "double taxation," or taxation at both the corporate and shareholder levels, that generally results from owning shares in a corporation. However, CubeSmart will be subject to federal tax in the following circumstances:

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        In addition, we may be subject to a variety of taxes, including payroll taxes and state, local and foreign income, property and other taxes on our assets and operations. We could also be subject to tax in situations and on transactions not presently contemplated.

        To qualify as a REIT, CubeSmart must elect to be treated as a REIT, and CubeSmart must meet various (a) organizational requirements, (b) gross income tests, (c) asset tests, and (d) annual distribution requirements.

        Organizational Requirements.    A REIT is a corporation, trust or association that meets each of the following requirements:

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        CubeSmart must meet requirements 1 through 4, 8 and 9 during its entire taxable year and must meet requirement 5 during at least 335 days of a taxable year of 12 months, or during a proportionate part of a taxable year of less than 12 months. If CubeSmart complies with all the requirements for ascertaining information concerning the ownership of its outstanding shares in a taxable year and has no reason to know that it violated requirement 6, CubeSmart will be deemed to have satisfied requirement 6 for that taxable year. CubeSmart's declaration of trust provides for restrictions regarding the ownership and transfer of its shares of beneficial interest that are intended to assist CubeSmart in continuing to satisfy requirements 5 and 6. However, these restrictions may not ensure that CubeSmart will, in all cases, be able to satisfy these requirements. The provisions of the declaration of trust restricting the ownership and transfer of its shares of beneficial interest are described in "Description of Our Shares—Restrictions on Ownership and Transfer."

        For purposes of determining share ownership under requirement 6, an "individual" generally includes a supplemental unemployment compensation benefits plan, a private foundation, or a portion of a trust permanently set aside or used exclusively for charitable purposes. An "individual," however, generally does not include a trust that is a qualified employee pension or profit sharing trust under the federal income tax laws, and beneficiaries of such a trust will be treated as holding CubeSmart's shares in proportion to their actuarial interests in the trust for purposes of requirement 6. CubeSmart believes it has issued sufficient shares of beneficial interest with enough diversity of ownership to satisfy requirements 5 and 6 set forth above.

        To monitor compliance with the share ownership requirements, CubeSmart is required to maintain records regarding the actual ownership of its shares. To do so, CubeSmart must demand written statements each year from the record holders of certain percentages of its shares in which the record holders are to disclose the actual owners of the shares (the persons required to include in gross income the dividends paid by us). A list of those persons failing or refusing to comply with this demand must be maintained as part of CubeSmart's records. Failure by CubeSmart to comply with these record-keeping requirements could subject CubeSmart to monetary penalties. If CubeSmart satisfies these requirements and has no reason to know that condition (6) is not satisfied, CubeSmart will be deemed to have satisfied such condition. A shareholder that fails or refuses to comply with the demand is required by Treasury Regulations to submit a statement with its tax return disclosing the actual ownership of the shares and other information.

        Qualified REIT Subsidiaries.    A corporation that is a "qualified REIT subsidiary" is not treated as a corporation separate from its parent REIT. A "qualified REIT subsidiary" is a corporation, all of the capital stock of which is owned by the REIT and that has not elected to be a taxable REIT subsidiary. All assets, liabilities, and items of income, deduction, and credit of a "qualified REIT subsidiary" are treated as assets, liabilities, and items of income, deduction, and credit of the REIT. Thus, in applying

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the requirements described herein, any "qualified REIT subsidiary" that CubeSmart owns will be ignored, and all assets, liabilities, and items of income, deduction, and credit of such subsidiary will be treated as Cubesmart's assets, liabilities, and items of income, deduction, and credit.

        Partnership Subsidiaries.    An unincorporated domestic entity, such as a partnership or limited liability company that has a single owner, generally is not treated as an entity separate from its parent for federal income tax purposes. An unincorporated domestic entity with two or more owners is generally treated as a partnership for federal income tax purposes. In the case of a REIT that is a partner in a partnership, the REIT is treated as owning its proportionate share of the assets of the partnership and as earning its allocable share of the gross income of the partnership for purposes of the applicable REIT qualification tests. Thus, CubeSmart's proportionate share of the assets, liabilities and items of income of the Operating Partnership and any other partnership, joint venture, or limited liability company that is treated as a partnership for federal income tax purposes in which CubeSmart acquires an interest, directly or indirectly, is treated as CubeSmart's assets and gross income for purposes of applying the various REIT qualification requirements.

        Taxable REIT Subsidiaries.    A REIT is permitted to own up to 100% of the stock of one or more "taxable REIT subsidiaries." A taxable REIT subsidiary is a corporation subject to U.S. federal income tax, and state and local income tax where applicable, as a regular "C" corporation. The subsidiary and the REIT must jointly elect to treat the subsidiary as a taxable REIT subsidiary. In addition, if a taxable REIT subsidiary owns, directly or indirectly, securities representing 35% or more of the vote or value of a subsidiary corporation, that subsidiary will also be treated as a taxable REIT subsidiary. Several provisions regarding the arrangements between a REIT and its taxable REIT subsidiaries ensure that a taxable REIT subsidiary will be subject to an appropriate level of United States federal income taxation. For example, the taxable REIT subsidiary rules limit the deductibility of interest paid or accrued by a taxable REIT subsidiary to its parent REIT. Further, the rules impose a 100% excise tax on transactions between a taxable REIT subsidiary and its parent REIT or the REIT's tenants that are not conducted on an arm's-length basis. CubeSmart may engage in activities indirectly through a taxable REIT subsidiary that would jeopardize its REIT status if CubeSmart engaged in the activities directly. For example, a taxable REIT subsidiary of CubeSmart may provide services to unrelated parties which might produce income that does not qualify under the gross income tests described below. A taxable REIT subsidiary may also engage in other activities that, if conducted by CubeSmart directly, could result in the receipt of non-qualified income or the ownership of non-qualified assets or the imposition of the 100% tax on income from prohibited transactions. See description below under "Prohibited Transactions."

        Gross Income Tests.    CubeSmart must satisfy two gross income tests annually to maintain its qualification as a REIT. First, at least 75% of its gross income for each taxable year must consist of defined types of income that CubeSmart derives, directly or indirectly, from investments relating to real property or mortgages on real property or qualified temporary investment income. Qualifying income for purposes of that 75% gross income test generally includes:

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        Second, in general, at least 95% of CubeSmart's gross income for each taxable year must consist of income that is qualifying income for purposes of the 75% gross income test, other types of interest and dividends (including dividends from its taxable REIT subsidiaries), gain from the sale or disposition of stock or securities, or any combination of these. Gross income from the sale of property that CubeSmart holds primarily for sale to customers in the ordinary course of business is excluded from both the numerator and the denominator in both income tests. See "Prohibited Transactions." In addition, certain gains from hedging transactions and certain foreign currency gains will be excluded from both the numerator and the denominator for purposes of one or both of the income tests. See "Hedging Transactions," and "Foreign Currency Gain."

        Rents from Real Property.    Rent that CubeSmart receives from its real property will qualify as "rents from real property," which is qualifying income for purposes of the 75% and 95% gross income tests, only if the following conditions are met:

        First, the rent must not be based in whole or in part on the income or profits of any person. Participating rent, however, will qualify as "rents from real property" if it is based on percentages of receipts or sales and the percentages are fixed at the time the leases are entered into, are not renegotiated during the term of the leases in a manner that has the effect of basing percentage rent on income or profits, and conform with normal business practice.

        Second, CubeSmart must not own, actually or constructively, 10% or more of the stock of any corporate tenant or the assets or net profits of any tenant, referred to as a related party tenant, other than a taxable REIT subsidiary. The constructive ownership rules generally provide that, if 10% or more in value of its shares is owned, directly or indirectly, by or for any person, CubeSmart is considered as owning the stock owned, directly or indirectly, by or for such person. CubeSmart does not own any stock or any assets or net profits of any tenant directly. However, because the constructive ownership rules are broad and it is not possible to monitor continually direct and indirect transfers of its shares, no absolute assurance can be given that such transfers or other events of which CubeSmart has no knowledge will not cause CubeSmart to own constructively 10% or more of a tenant (or a subtenant, in which case only rent attributable to the subtenant is disqualified) other than a taxable REIT subsidiary at some future date.

        Under an exception to the related-party tenant rule described in the preceding paragraph, rent that CubeSmart receives from a taxable REIT subsidiary will qualify as "rents from real property" as long as (1) at least 90% of the leased space in the property is leased to persons other than taxable REIT subsidiaries and related-party tenants, and (2) the amount paid by the taxable REIT subsidiary to rent space at the property is substantially comparable to rents paid by other tenants of the property for comparable space. The "substantially comparable" requirement must be satisfied when the lease is entered into, when it is extended, and when the lease is modified, if the modification increases the rent paid by the taxable REIT subsidiary. If the requirement that at least 90% of the leased space in the related property is rented to unrelated tenants is met when a lease is entered into, extended, or modified, such requirement will continue to be met as long as there is no increase in the space leased to any taxable REIT subsidiary or related party tenant. Any increased rent attributable to a modification of a lease with a taxable REIT subsidiary in which CubeSmart owns directly or indirectly more than 50% of the voting power or value of the stock (a "controlled taxable REIT subsidiary") will not be treated as "rents from real property."

        Third, the rent attributable to the personal property leased in connection with a lease of real property must not be greater than 15% of the total rent received under the lease. The rent attributable

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to personal property under a lease is the amount that bears the same ratio to total rent under the lease for the taxable year as the average of the fair market values of the leased personal property at the beginning and at the end of the taxable year bears to the average of the aggregate fair market values of both the real and personal property covered by the lease at the beginning and at the end of such taxable year (the "personal property ratio"). With respect to each of its leases, CubeSmart believes that the personal property ratio generally is less than 15%. Where that is not, or may in the future not be, the case, CubeSmart believes that any income attributable to personal property will not jeopardize its ability to qualify as a REIT. There can be no assurance, however, that the IRS would not challenge CubeSmart's calculation of a personal property ratio, or that a court would not uphold such assertion. If such a challenge were successfully asserted, CubeSmart could fail to satisfy the 75% or 95% gross income test and thus lose its REIT status.

        Fourth, CubeSmart cannot furnish or render non-customary services to the tenants of its properties, or manage or operate its properties, other than through an independent contractor who is adequately compensated and from whom CubeSmart does not derive or receive any income. However, CubeSmart need not provide services through an "independent contractor," but instead may provide services directly to its tenants, if the services are "usually or customarily rendered" in connection with the rental of space for occupancy only and are not considered to be provided for the tenants' convenience. In addition, CubeSmart may provide a minimal amount of "non-customary" services to the tenants of a property, other than through an independent contractor, as long as its income (valued at not less than 150% of our direct cost of performing such services) from the services does not exceed 1% of its income from the related property. Such income will not cause rents from tenants of the property to qualify as rents from real property but income from such services will not qualify as rents from real property. Finally, CubeSmart may own up to 100% of the stock of one or more taxable REIT subsidiaries, which may provide non-customary services to CubeSmart's tenants without tainting CubeSmart's rents from the related properties. CubeSmart has not performed, and does not intend to perform, any services other than customary ones for its tenants, other than services provided through independent contractors or taxable REIT subsidiaries.

        Tenants may be required to pay, in addition to base rent, reimbursements for certain amounts CubeSmart is obligated to pay to third parties (such as a lessee's proportionate share of a property's operational or capital expenses), penalties for nonpayment or late payment of rent or additions to rent. These and other similar payments should qualify as "rents from real property." To the extent they do not, they should be treated as interest that qualifies for the 95% gross income test.

        If a portion of the rent CubeSmart receives from a property does not qualify as "rents from real property" because the rent attributable to personal property exceeds 15% of the total rent for a taxable year, the portion of the rent attributable to personal property will not be qualifying income for purposes of either the 75% or 95% gross income test. Thus, if rent attributable to personal property, plus any other income that is nonqualifying income for purposes of the 95% gross income test, during a taxable year exceeds 5% of its gross income during the year, CubeSmart would lose its REIT status, unless CubeSmart qualified for certain statutory relief provisions. By contrast, in the following circumstances, none of the rent from a lease of property would qualify as "rents from real property": (1) the rent is considered based on the income or profits of the tenant; (2) the lessee is a related party tenant or fails to qualify for the exception to the related-party tenant rule for qualifying taxable REIT subsidiaries; or (3) CubeSmart furnishes non-customary services to the tenants of the property, or manages or operates the property, other than through a qualifying independent contractor or a taxable REIT subsidiary. In any of these circumstances, CubeSmart could lose its REIT status, unless CubeSmart qualified for certain statutory relief provisions, because it would be unable to satisfy either the 75% or 95% gross income test.

        Interest.    The term "interest" generally does not include any amount received or accrued, directly or indirectly, if the determination of the amount depends in whole or in part on the income or profits

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of any person. However, an amount received or accrued generally will not be excluded from the term "interest" solely because it is based on a fixed percentage or percentages of receipts or sales. Furthermore, to the extent that interest from a loan that is based on the profit or net cash proceeds from the sale of the property securing the loan constitutes a "shared appreciation provision," income attributable to such participation feature will be treated as gain from the sale of the secured property.

        Dividends.    Our share of dividends received from any corporation (including any TRS, but excluding any REIT) in which we own any equity interest will qualify for purposes of the 95% gross income test but not for purposes of the 75% gross income test. Our share of any dividends received from any other REIT in which we own an equity interest, if any, will be qualifying income for purposes of both income tests.

        Prohibited Transactions.    A REIT will incur a 100% tax on the net income derived from any sale or other disposition of property, other than foreclosure property, that the REIT holds primarily for sale to customers in the ordinary course of a trade or business. Whether a REIT holds an asset "primarily for sale to customers in the ordinary course of a trade or business" depends, however, on the facts and circumstances in effect from time to time, including those related to a particular asset. A safe harbor to the characterization of the sale of property by a REIT as a prohibited transaction and the 100% prohibited transaction tax is available if the following requirements are met:

        CubeSmart intends to hold properties for investment with a view to long-term appreciation, to engage in the business of acquiring, developing, owning and operating properties, and to make occasional sales of properties as are consistent with its investment objective. CubeSmart cannot assure you, however, that it can comply with the safe-harbor provisions that would prevent the imposition of the 100% tax or that it will avoid owning property that may be characterized as property held "primarily for sale to customers in the ordinary course of a trade or business." The 100% tax does not apply to gains from the sale of property that is held through a taxable REIT subsidiary or other taxable corporation, although such income will be subject to tax in the hands of that corporation at regular corporate tax rates. CubeSmart may, therefore, form or acquire a taxable REIT subsidiary to hold and dispose of those properties it concludes may not fall within the safe-harbor provisions.

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        Foreclosure Property.    CubeSmart will be subject to tax at the maximum corporate rate on any net income from foreclosure property, other than income that otherwise would be qualifying income for purposes of the 75% gross income test. "Foreclosure property" is any real property, including interests in real property, and any personal property incident to such real property:

        A REIT will not be considered to have foreclosed on a property where the REIT takes control of the property as a mortgagee-in-possession and cannot receive any profit or sustain any loss except as a creditor of the mortgagor. Property generally ceases to be foreclosure property at the end of the third taxable year following the taxable year in which the REIT acquired the property (or longer if an extension is granted by the Secretary of the Treasury). This period (as extended, if applicable) terminates, and foreclosure property ceases to be foreclosure property on the first day:

        Any gain from the sale of property for which a foreclosure property election has been made will not be subject to the 100% tax on gains from prohibited transactions described above, even if the property is held primarily for sale to customers in the ordinary course of a trade or business. Income and gain from foreclosure property are qualifying income for the 75% and 95% gross income tests.

        Hedging Transactions.    From time to time, CubeSmart enters into hedging transactions with respect to its assets or liabilities. CubeSmart's hedging activities may include entering into interest rate swaps, caps, and floors, options to purchase such items, and futures and forward contracts. Income and gain from "hedging transactions" will be excluded from gross income for purposes of both the 75% and 95% gross income tests. A "hedging transaction" means either (1) any transaction entered into in the normal course of its trade or business primarily to manage the risk of interest rate, price changes, or currency fluctuations with respect to borrowings made or to be made, or ordinary obligations incurred or to be incurred, to acquire or carry real estate assets or (2) for transactions entered into after July 30, 2008, any transaction entered into primarily to manage the risk of currency fluctuations with respect to any item of income or gain that would be qualifying income under the 75% or 95% gross income test (or any property which generates such income or gain). CubeSmart will be required to clearly identify any such hedging transaction before the close of the day on which it was acquired, originated, or entered into and to satisfy other identification requirements. No assurance can be given that its hedging activities will not give rise to income that does not qualify for purposes of either or both of the gross income tests, and will not adversely affect CubeSmart's ability to satisfy the REIT qualification requirements.

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        Foreign Currency Gain.    Certain foreign currency gains recognized after July 30, 2008 will be excluded from gross income for purposes of one or both of the gross income tests. "Real estate foreign exchange gain" will be excluded from gross income for purposes of the 75% gross income test. Real estate foreign exchange gain generally includes foreign currency gain attributable to any item of income or gain that is qualifying income for purposes of the 75% gross income test, foreign currency gain attributable to the acquisition or ownership of (or becoming or being the obligor under) obligations secured by mortgages on real property or on interests in real property and certain foreign currency gain attributable to certain "qualified business units" of a REIT. "Passive foreign exchange gain" will be excluded from gross income for purposes of the 95% gross income test. Passive foreign exchange gain generally includes real estate foreign exchange gain as described above, and also includes foreign currency gain attributable to any item of income or gain that is qualifying income for purposes of the 95% gross income test and foreign currency gain attributable to the acquisition or ownership of (or becoming or being the obligor under) debt obligations. Because passive foreign exchange gain includes real estate foreign exchange gain, real estate foreign exchange gain is excluded from gross income for purposes of both the 75% and 95% gross income test. These exclusions for real estate foreign exchange gain and passive foreign exchange gain do not apply to foreign currency gain derived from dealing, or engaging in substantial and regular trading, in securities. Such gain is treated as nonqualifying income for purposes of both the 75% and 95% gross income tests.

        Failure to Satisfy Gross Income Tests.    If CubeSmart fails to satisfy one or both of the gross income tests for any taxable year, CubeSmart nevertheless may qualify as a REIT for that year if it qualifies for relief under certain provisions of the federal income tax laws. Those relief provisions will be available if:

        CubeSmart cannot predict, however, whether any failure to meet these tests will qualify for the relief provisions. As discussed above in "Taxation of CubeSmart as a REIT," even if the relief provisions apply, CubeSmart would incur a 100% tax on the gross income attributable to the greater of (1) the amount by which it fails the 75% gross income test, or (2) the excess of 95% of its gross income over the amount of gross income qualifying under the 95% gross income test, multiplied, in either case, by a fraction intended to reflect its profitability.

        Asset Tests.    To maintain its qualification as a REIT, CubeSmart also must satisfy the following asset tests at the end of each quarter of each taxable year.

        First, at least 75% of the value of CubeSmart's total assets must consist of:

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        Second, of CubeSmart's investments not included in the 75% asset class, the value of its interest in any one issuer's securities may not exceed 5% of the value of its total assets, or the "5% asset test."

        Third, of CubeSmart's investments not included in the 75% asset class, CubeSmart may not own more than 10% of the voting power or value of any one issuer's outstanding securities, or the "10% vote test" and "10% value test," respectively.

        Fourth, no more than 20% of the value of CubeSmart's total assets (or, beginning with its 2009 taxable year, 25% of the value of its total assets) may consist of the securities of one or more taxable REIT subsidiaries.

        For purposes of the 5% asset test, the 10% vote test and 10% value test, the term "securities" does not include stock in another REIT, equity or debt securities of a qualified REIT subsidiary or taxable REIT subsidiary, mortgage loans that constitute real estate assets, or equity interests in a partnership. The term "securities," however, generally includes debt securities issued by a partnership or another REIT, except that for purposes of the 10% value test, the term "securities" does not include:

        For purposes of the 10% value test, its proportionate share of the assets of a partnership is its proportionate interest in any securities issued by the partnership, without regard to the securities described in the last two bullet points above.

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        Failure to Satisfy Asset Tests.    CubeSmart will monitor the status of its assets for purposes of the various asset tests and will manage its portfolio in order to comply at all times with such tests. If CubeSmart fails to satisfy the asset tests at the end of a calendar quarter, it would not lose its REIT status if:

        If the failure to satisfy the asset tests results from an acquisition of securities or other property during a quarter, the failure can be cured by disposition of sufficient nonqualifying assets within 30 days after the close of that quarter. CubeSmart intends to maintain adequate records of the value of its assets to ensure compliance with the asset tests, and to take such other action within 30 days after the close of any quarter as may be required to cure any noncompliance. However, there can be no assurance that such other action will always be successful. If CubeSmart fails to cure any noncompliance with the asset tests within such time period, its status as a REIT would be lost.

        In the event that, at the end of any calendar quarter, CubeSmart violates the 5% asset test, the 10% vote test or the 10% value test described above, CubeSmart will not lose its REIT status if (i) the failure is de minimis (up to the lesser of 1% of its assets or $10 million) and (ii) CubeSmart disposes of assets or otherwise complies with the asset tests within six months after the last day of the quarter in which it identifies such failure. In the event the failure to meet the asset test is more than de minimis, CubeSmart will not lose its REIT status if (i) the failure was due to reasonable cause and not to willful neglect, (ii) CubeSmart files a description of each asset causing the failure with the IRS, (iii) CubeSmart disposes of assets or otherwise complies with the asset tests within six months after the last day of the quarter in which CubeSmart identifies the failure, and (iv) CubeSmart pays a tax equal to the greater of $50,000 or 35% of the net income from the nonqualifying assets during the period in which it failed to satisfy the asset tests.

        Annual Distribution Requirements.    Each taxable year, CubeSmart must distribute dividends, other than capital gain dividends and deemed distributions of retained capital gain, to its shareholders in an aggregate amount not less than the sum of

        Generally, CubeSmart must pay such distributions in the taxable year to which they relate, or in the following taxable year if either (a) CubeSmart declares the distribution before it timely files its federal income tax return for the year and pays the distribution on or before the first regular dividend payment date after such declaration or (b) CubeSmart declares the distribution in October, November, or December of the taxable year, payable to shareholders of record on a specified day in any such month, and CubeSmart actually pays the dividend before the end of January of the following year. In both instances, these distributions relate to its prior taxable year for purposes of the 90% distribution requirement.

        In order for distributions to be counted towards CubeSmart's distribution requirement, and to provide a tax deduction to CubeSmart, they must not be "preferential dividends." A dividend is not a preferential dividend if it is pro rata among all outstanding shares within a particular class, and is in accordance with the preferences among the different classes of shares as set forth in CubeSmart's organizational documents.

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        To the extent that CubeSmart distributes at least 90%, but less than 100%, of its net taxable income, CubeSmart will be subject to tax at ordinary corporate tax rates on the retained portion. In addition, CubeSmart may elect to retain, rather than distribute, its net long-term capital gains and pay tax on such gains. In this case, CubeSmart would elect to have its shareholders include their proportionate share of such undistributed long-term capital gains in their income and receive a corresponding credit for their proportionate share of the tax paid by us. CubeSmart's shareholders would then increase their adjusted basis in their CubeSmart shares by the difference between the amount included in their long-term capital gains and the tax deemed paid with respect to their shares.

        If CubeSmart fails to distribute during a calendar year, or by the end of January of the following calendar year in the case of distributions with declaration and record dates falling in the last three months of the calendar year, at least the sum of:

CubeSmart will incur a 4% nondeductible excise tax on the excess of such required distribution over the amounts CubeSmart actually distributed. If CubeSmart so elects, it will be treated as having distributed any such retained amount for purposes of the 4% nondeductible excise tax described above.

        It is possible that, from time to time, CubeSmart may experience timing differences between the actual receipt of income and actual payment of deductible expenses and the inclusion of that income and deduction of such expenses in arriving at its REIT taxable income. For example, because CubeSmart may deduct capital losses only to the extent of its capital gains, its REIT taxable income may exceed its economic income. Further, it is possible that, from time to time, CubeSmart may be allocated a share of net capital gain from a partnership in which CubeSmart owns an interest attributable to the sale of depreciated property that exceeds its allocable share of cash attributable to that sale. Although several types of non-cash income are excluded in determining the annual distribution requirement, CubeSmart will incur corporate income tax and the 4% nondeductible excise tax with respect to those non-cash income items if CubeSmart does not distribute those items on a current basis. As a result of the foregoing, CubeSmart may have less cash than is necessary to distribute all of its taxable income and thereby avoid corporate income tax and the 4% nondeductible excise tax imposed on certain undistributed income. In such a situation, CubeSmart may issue additional common or preferred shares, CubeSmart may borrow or may cause the Operating Partnership to arrange for short-term or possibly long-term borrowing to permit the payment of required distributions, or CubeSmart may pay dividends in the form of taxable in-kind distributions of property, including potentially, its shares.

        Under certain circumstances, CubeSmart may be able to correct a failure to meet the distribution requirement for a year by paying "deficiency dividends" to its shareholders in a later year. CubeSmart may include such deficiency dividends in its deduction for dividends paid for the earlier year. Although CubeSmart may be able to avoid income tax on amounts distributed as deficiency dividends, CubeSmart will be required to pay interest to the IRS based upon the amount of any deduction it takes for deficiency dividends.

        Recordkeeping Requirements.    CubeSmart must maintain certain records in order to qualify as a REIT. In addition, to avoid paying a penalty, CubeSmart must request on an annual basis information from its shareholders designed to disclose the actual ownership of its outstanding common shares and preferred shares.

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        If CubeSmart were to fail to qualify as a REIT in any taxable year and no relief provision applied, CubeSmart would have the following consequences: CubeSmart would be subject to federal income tax and any applicable alternative minimum tax at regular corporate rates applicable to regular C corporations on its taxable income, determined without reduction for amounts distributed to shareholders. CubeSmart would not be required to make any distributions to shareholders. Unless CubeSmart qualified for relief under specific statutory provisions, it would not be permitted to elect taxation as a REIT for the four taxable years following the year during which CubeSmart ceased to qualify as a REIT.

        If CubeSmart fails to satisfy one or more requirements for REIT qualification, other than the gross income tests and the asset tests, CubeSmart could avoid disqualification if its failure is due to reasonable cause and not to willful neglect and CubeSmart pays a penalty of $50,000 for each such failure. In addition, there are relief provisions for a failure of the gross income tests and asset tests, as described in "Requirements for Qualification—Gross Income Tests" and "Requirements for Qualification—Asset Tests." It is not possible to state whether in all circumstances CubeSmart would be entitled to such statutory relief.

        We may be subject to taxation by various states and localities, including those in which we transact business or own property. The state and local tax treatment in such jurisdictions may differ from the federal income tax treatment described above.

        The following discussion summarizes certain federal income tax considerations applicable to CubeSmart's direct or indirect investment in its Operating Partnership and any subsidiary partnerships or limited liability companies we form or acquire that are treated as partnerships for federal income tax purposes, each individually referred to as a "Partnership" and, collectively, as "Partnerships." The following discussion does not address state or local tax laws or any federal tax laws other than income tax laws.

        Classification as Partnerships.    CubeSmart is required to include in its income its distributive share of each Partnership's income and to deduct its distributive share of each Partnership's losses but only if such Partnership is classified for federal income tax purposes as a partnership (or an entity that is disregarded for federal income tax purposes if the entity has only one owner or member), rather than as a corporation or an association taxable as a corporation.

        An organization with at least two owners or members will be classified as a partnership, rather than as a corporation, for federal income tax purposes if it:

        Under the check-the-box regulations, an unincorporated domestic entity with at least two owners or members may elect to be classified either as an association taxable as a corporation or as a partnership. If such an entity does not make an election, it generally will be treated as a partnership for federal income tax purposes. We intend that each Partnership will be classified as a partnership for federal income tax purposes (or else a disregarded entity where there are not at least two separate beneficial owners).

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        A publicly traded partnership is a partnership whose interests are traded on an established securities market or are readily tradable on a secondary market (or a substantial equivalent). A publicly traded partnership is generally treated as a corporation for federal income tax purposes, but will not be so treated if, for each taxable year beginning after December 31, 1987 in which it was classified as a publicly traded partnership, at least 90% of the partnership's gross income consisted of specified passive income, including real property rents (which includes rents that would be qualifying income for purposes of the 75% gross income test, with certain modifications that make it easier for the rents to qualify for the 90% passive income exception), gains from the sale or other disposition of real property, interest, and dividends (the "90% passive income exception").

        Treasury regulations, referred to as PTP regulations, provide limited safe harbors from treatment as a publicly traded partnership. Pursuant to one of those safe harbors (the "private placement exclusion"), interests in a partnership will not be treated as readily tradable on a secondary market or the substantial equivalent thereof if (1) all interests in the partnership were issued in a transaction or transactions that were not required to be registered under the Securities Act of 1933, as amended, and (2) the partnership does not have more than 100 partners at any time during the partnership's taxable year. For the determination of the number of partners in a partnership, a person owning an interest in a partnership, grantor trust, or S corporation that owns an interest in the partnership is treated as a partner in the partnership only if (1) substantially all of the value of the owner's interest in the entity is attributable to the entity's direct or indirect interest in the partnership and (2) a principal purpose of the use of the entity is to permit the partnership to satisfy the 100-partner limitation. CubeSmart believes that each Partnership should qualify for the private placement exclusion.

        We have not requested, and do not intend to request, a ruling from the IRS that the Partnerships will be classified as partnerships (or disregarded entities, if the entity has only one owner or member) for federal income tax purposes. If for any reason a Partnership were taxable as a corporation, rather than as a partnership, for federal income tax purposes, CubeSmart may not be able to qualify as a REIT, unless it qualifies for certain relief provisions. See "Requirements for Qualification—Gross Income Tests" and "Requirements for Qualification—Asset Tests." In addition, any change in a Partnership's status for tax purposes might be treated as a taxable event, in which case CubeSmart might incur tax liability without any related cash distribution. See "Requirements for Qualification—Annual Distribution Requirements." Further, items of income and deduction of such Partnership would not pass through to its partners, and its partners would be treated as shareholders for tax purposes. Consequently, such Partnership would be required to pay income tax at corporate rates on its net income, and distributions to its partners would constitute dividends that would not be deductible in computing such Partnership's taxable income.

        Partners, Not the Partnerships, Subject to Tax.    A partnership is not a taxable entity for federal income tax purposes. CubeSmart will therefore take into account its allocable share of each Partnership's income, gains, losses, deductions, and credits for each taxable year of the Partnership ending with or within CubeSmart's taxable year, even if CubeSmart receives no distribution from the Partnership for that year or a distribution less than CubeSmart's share of taxable income. Similarly, even if CubeSmart receives a distribution, CubeSmart may not be taxable if the distribution does not exceed its adjusted tax basis in its interest in the Partnership.

        Partnership Allocations.    Although a partnership agreement generally will determine the allocation of income and losses among partners, allocations will be disregarded for tax purposes if they do not comply with the provisions of the federal income tax laws governing partnership allocations. If an allocation is not recognized for federal income tax purposes, the item subject to the allocation will be reallocated in accordance with the partners' interests in the partnership, which will be determined by taking into account all of the facts and circumstances relating to the economic arrangement of the partners with respect to such item.

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        Tax Allocations With Respect to Contributed Properties.    Income, gain, loss, and deduction attributable to (a) appreciated or depreciated property that is contributed to a partnership in exchange for an interest in the partnership or (b) property revalued on the books of a partnership must be allocated in a manner such that the contributing partner is charged with, or benefits from, respectively, the unrealized gain or unrealized loss associated with the property at the time of the contribution. The amount of such unrealized gain or unrealized loss, referred to as "built-in gain" or "built-in loss," is generally equal to the difference between the fair market value of the contributed or revalued property at the time of contribution or revaluation and the adjusted tax basis of such property at that time, referred to as a book-tax difference. Such allocations are solely for federal income tax purposes and do not affect the book capital accounts or other economic or legal arrangements among the partners. The U.S. Treasury Department has issued regulations requiring partnerships to use a "reasonable method" for allocating items with respect to which there is a book-tax difference and outlining several reasonable allocation methods. Unless we, as general partner, select a different method, the Operating Partnership will use the traditional method for allocating items with respect to which there is a book-tax difference. Depending upon the method chosen, (1) CubeSmart's tax depreciation deductions attributable to those properties may be lower than they would have been if the partnership had acquired those properties for cash and (2) in the event of a sale of such properties, CubeSmart could be allocated gain in excess of its corresponding economic or book gain. These allocations may cause CubeSmart to recognize taxable income in excess of cash proceeds received by us, which might adversely affect CubeSmart's ability to comply with the REIT distribution requirements or result in CubeSmart's shareholders recognizing additional dividend income without an increase in distributions.

        Depreciation.    Some assets in our Partnerships include appreciated property contributed by its partners. Assets contributed to a Partnership in a tax-free transaction generally retain the same depreciation method and recovery period as they had in the hands of the partner who contributed them to the partnership. Accordingly, the Partnership's depreciation deductions for such contributed real property are based on the historic tax depreciation schedules for the properties prior to their contribution to the Operating Partnership.

        Basis in Partnership Interest.    CubeSmart's adjusted tax basis in any partnership interest it owns generally will be:

        Loss allocated to CubeSmart in excess of its basis in a partnership interest will not be taken into account until CubeSmart again has basis sufficient to absorb the loss. A reduction of CubeSmart's share of partnership indebtedness will be treated as a constructive cash distribution to CubeSmart, and will reduce its adjusted tax basis in the partnership. Distributions, including constructive distributions, in excess of the basis of CubeSmart's partnership interest will constitute taxable income to CubeSmart. Such distributions and constructive distributions normally will be characterized as long-term capital gain.

        Sale of a Partnership's Property.    Generally, any gain realized by a Partnership on the sale of property held for more than one year will be long-term capital gain, except for any portion of the gain treated as depreciation or cost recovery recapture. Any gain or loss recognized by a Partnership on the disposition of contributed or revalued properties will be allocated first to the partners who contributed

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the properties or who were partners at the time of revaluation, to the extent of their built-in gain or loss on those properties for federal income tax purposes. The partners' built-in gain or loss on contributed or revalued properties is the difference between the partners' proportionate share of the book value of those properties and the partners' tax basis allocable to those properties at the time of the contribution or revaluation. Any remaining gain or loss recognized by the Partnership on the disposition of contributed or revalued properties, and any gain or loss recognized by the Partnership on the disposition of other properties, will be allocated among the partners in accordance with their percentage interests in the Partnership.

        CubeSmart's share of any Partnership gain from the sale of inventory or other property held primarily for sale to customers in the ordinary course of the Partnership's trade or business will be treated as income from a prohibited transaction subject to a 100% tax. Income from a prohibited transaction may have an adverse effect on CubeSmart's ability to satisfy the gross income tests for REIT status. See "Requirements for Qualification—Gross Income Tests." CubeSmart does not presently intend to acquire or hold, or to allow any Partnership to acquire or hold, any property that is likely to be treated as inventory or property held primarily for sale to customers in the ordinary course of CubeSmart's, or the Partnership's, trade or business.

Taxation of Shareholders

        The term "U.S. shareholder" means a beneficial owner of CubeSmart common shares or preferred shares that, for U.S. federal income tax purposes, is:

        If a partnership, entity or arrangement treated as a partnership for federal income tax purposes holds CubeSmart common shares or preferred shares, the federal income tax treatment of a partner in the partnership will generally depend on the status of the partner and the activities of the partnership. If you are a partner in a partnership holding CubeSmart common shares or preferred shares, you should consult your tax advisor regarding the consequences of the ownership and disposition of CubeSmart common shares or preferred shares by the partnership.

        Taxation of U.S. Shareholders on Distributions.    As long as CubeSmart qualifies as a REIT, a taxable U.S. shareholder will be required to take into account as ordinary income distributions made out of CubeSmart's current or accumulated earnings and profits that CubeSmart does not designate as capital gain dividends or retained long-term capital gain. A U.S. shareholder will not qualify for the dividends-received deduction generally available to corporations. Dividends paid to a U.S. shareholder generally will not qualify for the preferential tax rate for "qualified dividend income" (20% maximum rate). Qualified dividend income generally includes dividends paid by domestic C corporations and certain qualified foreign corporations to most noncorporate U.S. shareholders. Because a REIT is not generally subject to federal income tax on the portion of its REIT taxable income distributed to its shareholders, CubeSmart's dividends generally will not be eligible for the preferential tax rate on

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qualified dividend income. As a result, CubeSmart's ordinary REIT dividends will be taxed at the higher rate applicable to ordinary income. Currently, the highest marginal individual income tax rate on ordinary income is 39.6%. However, the preferential tax rate for qualified dividend income will apply to CubeSmart's ordinary REIT dividends, if any, that are (i) attributable to dividends received by CubeSmart from non-REIT corporations, such as our taxable REIT subsidiaries, and (ii) attributable to income upon which CubeSmart has paid corporate income tax (e.g., to the extent that CubeSmart distributes less than 100% of CubeSmart's taxable income). In general, to qualify for the preferential tax rate on qualified dividend income, a U.S. shareholder must hold CubeSmart common shares or preferred shares for more than 60 days during the 121-day period beginning on the date that is 60 days before the date on which the common shares or preferred shares become ex-dividend.

        With respect to common shares, CubeSmart may distribute taxable dividends that are payable partly in cash and partly in CubeSmart common shares. Taxable U.S. shareholders receiving such dividends will be required to include the full amount of the dividends as ordinary income to the extent of CubeSmart's current and accumulated earnings and profits.

        Any distribution CubeSmart declares in October, November, or December of any year that is payable to a U.S. shareholder of record on a specified date in any of those months will be treated as paid by CubeSmart and received by the U.S. shareholder on December 31 of the year, provided CubeSmart actually pays the distribution during January of the following calendar year.

        Distributions to a U.S. shareholder which CubeSmart designates as capital gain dividends will generally be treated as long-term capital gain, without regard to the period for which the U.S. shareholder has held its common shares or preferred shares. In general, U.S. shareholders will be taxable on long term capital gains at a maximum rate of 20%, except that the portion of such gain that is attributable to depreciation recapture will be taxable at the maximum rate of 25%. A corporate U.S. shareholder, however, may be required to treat up to 20% of certain capital gain dividends as ordinary income.

        CubeSmart may elect to retain and pay income tax on the net long-term capital gain that CubeSmart receives in a taxable year. In that case, a U.S. shareholder would be taxed on its proportionate share of CubeSmart's undistributed long-term capital gain. The U.S. shareholder would receive a credit or refund for its proportionate share of the tax CubeSmart paid. The U.S. shareholder would increase the basis in its common shares or preferred shares by the amount of its proportionate share of CubeSmart's undistributed long-term capital gain, minus its share of the tax CubeSmart paid.

        A U.S. shareholder will not incur tax on a distribution in excess of CubeSmart's current and accumulated earnings and profits if the distribution does not exceed the adjusted basis of the U.S. shareholder's common shares or preferred shares. Instead, the distribution will reduce the adjusted basis of the shares, and any amount in excess of both CubeSmart's current and accumulated earnings and profits and the adjusted basis will be treated as capital gain, long-term if the shares have been held for more than one year, provided the shares are a capital asset in the hands of the U.S. shareholder.

        Shareholders may not include in their individual income tax returns any of CubeSmart's net operating losses or capital losses. Instead, these losses are generally carried over by CubeSmart for potential offset against CubeSmart's future income. Taxable distributions from CubeSmart and gain from the disposition of common shares or preferred shares will not be treated as passive activity income; and, therefore, shareholders generally will not be able to apply any "passive activity losses," such as losses from certain types of limited partnerships in which the shareholder is a limited partner, against such income. In addition, taxable distributions from CubeSmart and gain from the disposition of common shares or preferred shares generally will be treated as investment income for purposes of the investment interest limitations. CubeSmart will notify shareholders after the close of its taxable year as to the portions of the distributions attributable to that year that constitute ordinary income, return of capital, and capital gain.

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Taxation of U.S. Shareholders on the Disposition of Common and Preferred Shares.

        In general, a U.S. shareholder who is not a dealer in securities must treat any gain or loss realized upon a taxable disposition of CubeSmart's common or preferred shares as long-term capital gain or loss if the U.S. shareholder has held the shares for more than one year, and otherwise as short-term capital gain or loss. In general, a U.S. shareholder will realize gain or loss in an amount equal to the difference between the sum of the fair market value of any property and the amount of cash received in such disposition and the U.S. shareholder's adjusted tax basis. A U.S. shareholder's adjusted tax basis generally will equal the U.S. shareholder's acquisition cost, increased by the excess of net capital gains deemed distributed to the U.S. shareholder less tax deemed paid by it and reduced by any returns of capital. However, a U.S. shareholder must treat any loss upon a sale or exchange of common or preferred shares held by such shareholder for six months or less as a long-term capital loss to the extent of capital gain dividends and any actual or deemed distributions from CubeSmart that such U.S. shareholder treats as long-term capital gain. All or a portion of any loss that a U.S. shareholder realizes upon a taxable disposition of common or preferred shares may be disallowed if the U.S. shareholder purchases other common shares or preferred shares within 30 days before or after the disposition.

        If a U.S. shareholder recognizes a loss upon a subsequent disposition of CubeSmart shares in an amount that exceeds a prescribed threshold, it is possible that the provisions of Treasury Regulations involving "reportable transactions" could apply, with a resulting requirement to separately disclose the loss generating transactions to the IRS. While these regulations are directed towards "tax shelters," they are written broadly, and apply to transactions that would not typically be considered tax shelters. Significant penalties apply for failure to comply with these requirements. You should consult your tax advisors concerning any possible disclosure obligation with respect to the receipt or disposition of CubeSmart shares, or transactions that might be undertaken directly or indirectly by us. Moreover, you should be aware that CubeSmart and other participants in transactions involving CubeSmart (including our advisors) might be subject to disclosure or other requirements pursuant to these regulations.

        The tax-rate differential between capital gain and ordinary income for non-corporate taxpayers may be significant. A taxpayer generally must hold a capital asset for more than one year for gain or loss derived from its sale or exchange to be treated as long-term capital gain or loss. The highest marginal individual income tax rate is currently 39.6%. The maximum tax rate on long-term capital gain applicable to U.S. shareholders taxed at individual rates is 20%. The maximum tax rate on long-term capital gain from the sale or exchange of "section 1250 property" (i.e., generally, depreciable real property) is 25% to the extent the gain would have been treated as ordinary income if the property were "section 1245 property" (i.e., generally, depreciable personal property). CubeSmart generally may designate whether a distribution CubeSmart designates as capital gain dividends (and any retained capital gain that CubeSmart is deemed to distribute) is taxable to non-corporate shareholders at a 20% or 25% rate. The characterization of income as capital gain or ordinary income may affect the deductibility of capital losses. A non-corporate taxpayer may deduct capital losses not offset by capital gains against its ordinary income only up to a maximum of $3,000 annually. A non-corporate taxpayer may carry unused capital losses forward indefinitely. A corporate taxpayer must pay tax on its net capital gain at corporate ordinary-income rates. A corporate taxpayer may deduct capital losses only to the extent of capital gains, with unused losses carried back three years and forward five years.

        Whenever we redeem any preferred shares, the treatment accorded to any redemption by us for cash (as distinguished from a sale, exchange or other disposition) of our preferred shares to a U.S. shareholder of such preferred shares can only be determined on the basis of the particular facts as to each holder at the time of redemption. In general, a U.S. shareholder of our preferred shares will recognize capital gain or loss measured by the difference between the amount received by the holder of

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such shares upon the redemption and such holder's adjusted tax basis in the preferred shares redeemed (provided the preferred shares are held as a capital asset) if such redemption (i) is "substantially disproportionate" with respect to the holder's interest in all classes of our shares under Section 302 (b)(2) of the Code, (ii) results in a "complete termination" of the holder's interest in all classes of our shares under Section 302(b)(3) of the Code, or (iii) is "not essentially equivalent to a dividend" with respect to the holder of the preferred shares under Section 302(b)(1) of the Code. In applying these tests, there must be taken into account not only the preferred shares being redeemed, but also such holder's ownership of other classes and series of our shares and any options (including stock purchase rights) to acquire any of the foregoing. The U.S. shareholder of our preferred shares also must take into account any such securities (including options) which are considered to be owned by such holder by reason of the constructive ownership rules set forth in Sections 318 and 302(c) of the Code.

        If the U.S. shareholder of preferred shares owns (actually or constructively) none of our voting shares, or owns an insubstantial amount of our voting shares, based upon current law, it is probable that the redemption of preferred shares from such a holder would be considered to be "not essentially equivalent to a dividend." However, whether a distribution is "not essentially equivalent to a dividend" depends on all of the facts and circumstances, and a U.S. shareholder of our preferred shares intending to rely on any of the tests in this or the preceding paragraph at the time of redemption should consult its tax advisor to determine their application to its particular situation. If the redemption does not meet any of the tests under Section 302 of the Code, then the redemption proceeds received from our preferred shares will be treated as a distribution on our shares as described under "Taxation of U.S. Shareholders—Taxation of Taxable U.S. Shareholders—Taxation of U.S. Shareholders on Distributions." If the redemption of a holder's preferred shares is taxed as a dividend, the adjusted basis of such holder's redeemed preferred shares will be transferred to any other shares held by the holder. If the holder owns no other shares, under certain circumstances, such basis may be transferred to a related person, or it may be lost entirely.

        With respect to a redemption of our preferred shares that is treated as a distribution with respect to our shares, which is not otherwise taxable as a dividend, the IRS has proposed Treasury regulations that would require any basis reduction associated with such a redemption to be applied on a share-by-share basis which could result in taxable gain with respect to some shares, even though the holder's aggregate basis for the shares would be sufficient to absorb the entire amount of the redemption distribution (in excess of any amount of such distribution treated as a dividend). Additionally, these proposed Treasury regulations would not permit the transfer of basis in the redeemed shares of the preferred shares to the remaining shares held (directly or indirectly) by the redeemed holder. Instead, the unrecovered basis in our preferred shares would be treated as a deferred loss to be recognized when certain conditions are satisfied. These proposed Treasury regulations would be effective for transactions that occur after the date the regulations are published as final Treasury regulations. There can, however, be no assurance as to whether, when, and in what particular form such proposed Treasury regulations will ultimately be finalized.

        Except as provided below, a U.S. shareholder generally will not recognize gain or loss upon the conversion of our preferred shares into our common shares. Except as provided below, a U.S. shareholder's basis and holding period in the common shares received upon conversion generally will be the same as those of the converted preferred shares (but the basis will be reduced by the portion of adjusted tax basis allocated to any fractional common share exchanged for cash). Any common shares received in a conversion that is attributable to accumulated and unpaid dividends on the converted preferred shares will be treated as a distribution on our shares as described above in "Taxation of U.S. Shareholders—Taxation of Taxable U.S. Shareholders—Taxation of U.S. Shareholders on Distributions."

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Cash received upon conversion in lieu of a fractional common share generally will be treated as a payment in a taxable exchange for such fractional common share, and gain or loss will be recognized on the receipt of cash in an amount equal to the difference between the amount of cash received and the adjusted tax basis allocable to the fractional common share deemed exchanged. This gain or loss will be long-term capital gain or loss if the U.S. shareholder has held the preferred shares for more than one year. See "—Taxation of U.S. Shareholders—Taxation of Taxable U.S. Shareholders—Taxation of U.S. Shareholders on the Disposition of Common and Preferred Shares." U.S. shareholders should consult with their tax advisor regarding the U.S. federal income tax consequences of any transaction by which such holder exchanges common shares received on a conversion of preferred shares for cash or other property.

Information Reporting Requirements and Backup Withholding.

        CubeSmart will report to its shareholders and to the IRS the amount of distributions CubeSmart pays during each calendar year and the amount of tax it withholds, if any. A shareholder may be subject to backup withholding at a rate of up to 28% with respect to distributions unless the holder:

        A shareholder who does not provide CubeSmart with its correct taxpayer identification number also may be subject to penalties imposed by the IRS. In addition, CubeSmart may be required to withhold a portion of capital gain distributions to any shareholders who fail to certify their non-foreign status to CubeSmart. Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against the shareholder's income tax liability, provided the required information is furnished to the IRS.

        Tax-exempt entities, including qualified employee pension and profit sharing trusts and individual retirement accounts and annuities, generally are exempt from federal income taxation. However, they are subject to taxation on their "unrelated business taxable income." While many investments in real estate generate unrelated business taxable income, the IRS has issued a ruling that dividend distributions from a REIT to an exempt employee pension trust do not constitute unrelated business taxable income so long as the exempt employee pension trust does not otherwise use the shares of the REIT in an unrelated trade or business of the pension trust. Based on that ruling, amounts CubeSmart distributes to tax-exempt shareholders generally should not constitute unrelated business taxable income. However, if a tax-exempt shareholder were to finance its acquisition of common shares or preferred shares with debt, a portion of the income it received from CubeSmart would constitute unrelated business taxable income pursuant to the "debt-financed property" rules. Furthermore, social clubs, voluntary employee benefit associations, supplemental unemployment benefit trusts, and qualified group legal services plans that are exempt from taxation under special provisions of the federal income tax laws are subject to different unrelated business taxable income rules, which generally will require them to characterize distributions they receive from CubeSmart as unrelated business taxable income.

        In certain circumstances, a qualified employee pension or profit-sharing trust that owns more than 10% of CubeSmart's shares of beneficial interest (by value) must treat a percentage of the dividends it receives from CubeSmart as unrelated business taxable income. Such percentage is equal to the gross income CubeSmart derives from an unrelated trade or business, determined as if CubeSmart were a

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pension trust, divided by its total gross income for the year in which it pays the dividends. This rule applies to a pension trust holding more than 10% of CubeSmart shares only if:

        Certain restrictions on ownership and transfer of CubeSmart's shares should generally prevent a tax-exempt entity from owning more than 10% of the value of its shares, or CubeSmart from becoming a pension-held REIT.

        Tax-exempt U.S. shareholders are urged to consult their tax advisor regarding the U.S. federal, state, local and foreign tax consequences of the acquisition, ownership and disposition of CubeSmart shares.

        The term "non-U.S. shareholder" means a beneficial owner of CubeSmart common shares or preferred shares that is not a U.S. shareholder or a partnership (or an entity treated as a partnership for federal income tax purposes). The rules governing U.S. federal income taxation of non-U.S. shareholders are complex. This section is only a summary of such rules. We urge non-U.S. shareholders to consult their own tax advisors to determine the impact of federal, state, local and foreign income tax laws on ownership of common shares or preferred shares, including any reporting requirements.

        Taxation of Distributions.    A non-U.S. shareholder that receives a distribution which is not attributable to gain from CubeSmart's sale or exchange of a "United States real property interest" ("USRPI") (discussed below) and that CubeSmart does not designate a capital gain dividend or retained capital gain will recognize ordinary income to the extent that CubeSmart pays such distribution out of CubeSmart's current or accumulated earnings and profits. A withholding tax equal to 30% of the gross amount of the distribution ordinarily will apply unless an applicable tax treaty reduces or eliminates the tax. However, a non-U.S. shareholder generally will be subject to federal income tax at graduated rates on any distribution treated as effectively connected with the non-U.S. shareholder's conduct of a U.S. trade or business, in the same manner as U.S. shareholders are taxed on distributions. A corporate non-U.S. shareholder may, in addition, be subject to the 30% branch profits tax with respect to that distribution. CubeSmart plans to withhold U.S. income tax at the rate of 30% on the gross amount of any distribution paid to a non-U.S. shareholder unless either:

        A non-U.S. shareholder will not incur tax on a distribution in excess of CubeSmart's current and accumulated earnings and profits if the excess portion of such distribution does not exceed the adjusted basis of its common shares or preferred shares. Instead, the excess portion of the distribution will reduce the adjusted basis of such shares. A non-U.S. shareholder will be subject to tax on a distribution

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that exceeds both CubeSmart's current and accumulated earnings and profits and the adjusted basis of its shares, if the non-U.S. shareholder otherwise would be subject to tax on gain from the sale or disposition of common shares or preferred shares, as described below. Because CubeSmart generally cannot determine at the time CubeSmart makes a distribution whether the distribution will exceed CubeSmart's current and accumulated earnings and profits, CubeSmart normally will withhold tax on the entire amount of any distribution at the same rate as CubeSmart would withhold on a dividend. However, a non-U.S. shareholder may obtain a refund of amounts CubeSmart withholds if CubeSmart later determines that a distribution in fact exceeded CubeSmart's current and accumulated earnings and profits.

        CubeSmart may be required to withhold 10% of any distribution that exceeds CubeSmart's current and accumulated earnings and profits. Consequently, although CubeSmart intends to withhold at a rate of 30% on the entire amount of any distribution, to the extent CubeSmart does not do so, CubeSmart may withhold at a rate of 10% on any portion of a distribution not subject to withholding at a rate of 30%.

        For any year in which CubeSmart qualifies as a REIT, except as discussed below with respect to 5% or less holders of regularly traded classes of shares, a non-U.S. shareholder will incur tax on distributions attributable to gain from CubeSmart's sale or exchange of a USRPI under the Foreign Investment in Real Property Tax Act of 1980, or "FIRPTA." A USRPI includes certain interests in real property and shares in corporations at least 50% of whose assets consist of interests in real property. Under FIRPTA, a non-U.S. shareholder is taxed on distributions attributable to gain from sales of USRPIs as if the gain were effectively connected with the conduct of a U.S. business of the non-U.S. shareholder. A non-U.S. shareholder would be taxed on such a distribution at the normal capital gain rates applicable to U.S. shareholders, subject to applicable alternative minimum tax and a special alternative minimum tax in the case of a nonresident alien individual. A non-U.S. corporate shareholder not entitled to treaty relief or exemption also may be subject to the 30% branch profits tax on such a distribution. CubeSmart must withhold 35% of any distribution that CubeSmart could designate as a capital gain dividend. A non-U.S. shareholder may receive a credit against its tax liability for the amount CubeSmart withholds.

        However, distributions attributable to gain from sales or exchanges by CubeSmart of USRPIs are treated as ordinary dividends (not subject to the 35% withholding tax under FIRPTA) if the distribution is made to a non-U.S. shareholder with respect to any class of shares which is "regularly traded" on an established securities market located in the United States and if the non-U.S. shareholder did not own more than 5% of such class of shares at any time during the taxable year. Such distributions will generally be subject to a 30% U.S. withholding tax (subject to reduction under applicable treaty) and a non-U.S. shareholder will not be required to report the distribution on a U.S. tax return. In addition, the branch profits tax will not apply to such distributions.

        Taxation of Disposition of Shares.    A non-U.S. shareholder generally will not incur tax under FIRPTA with respect to gain on a sale of common shares or preferred shares as long as CubeSmart is a "domestically-controlled REIT," which means that at all times non-U.S. persons hold, directly or indirectly, less than 50% in value of all outstanding CubeSmart shares. CubeSmart cannot assure you that this test will be met. Further, even if CubeSmart is a domestically controlled REIT, pursuant to "wash sale" rules under FIRPTA, a non-U.S. shareholder may incur tax under FIRPTA. The "wash sale" rule applies to the extent such non-U.S. shareholder disposes of CubeSmart shares during the 30-day period preceding a dividend payment, and such non-U.S. shareholder (or a person related to such non-U.S. shareholder) acquires or enters into a contract or option to acquire CubeSmart common shares or preferred shares within 61 days of the 1st day of the 30 day period described above, and any portion of such dividend payment would, but for the disposition, be treated as a USRPI capital gain to such non-U.S. shareholder, then such non-U.S. shareholder shall be treated as having USRPI capital gain in an amount that, but for the disposition, would have been treated as USRPI capital gain.

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        In addition, a non-U.S. shareholder that owned, actually or constructively, 5% or less of the outstanding common shares or preferred shares at all times during a specified testing period will not incur tax under FIRPTA on gain from a sale of such common shares or preferred shares if such shares are "regularly traded" on an established securities market. Because CubeSmart's common shares and preferred shares are "regularly traded" on an established securities market, CubeSmart expects that a non-U.S. shareholder generally will not incur tax under FIRPTA on gain from a sale of common shares or preferred shares unless it owns or has owned more than 5% of such common shares or preferred shares at any time during the five year period to such sale. Any gain subject to tax under FIRPTA will be treated in the same manner as it would be in the hands of U.S. shareholders, subject to alternative minimum tax, but under a special alternative minimum tax in the case of nonresident alien individuals, and the purchaser of the shares could be required to withhold 10% of the purchase price and remit such amount to the IRS.

        A non-U.S. shareholder generally will incur tax on gain not subject to FIRPTA if:

        Redemptions of Our Preferred Shares.    Whenever we redeem any preferred shares, the treatment accorded to any redemption by us for cash (as distinguished from a sale, exchange or other disposition) of our preferred shares to a non-U.S. shareholder of such preferred shares can only be determined on the basis of the particular facts as to each holder at the time of redemption. In general, a non-U.S. shareholder of our preferred shares will recognize capital gain or loss measured by the difference between the amount received by the holder of such shares upon the redemption and such holder's adjusted tax basis in the preferred shares redeemed (provided the preferred shares are held as a capital asset) if such redemption (i) is "substantially disproportionate" with respect to the holder's interest in all classes of our shares under Section 302 (b)(2) of the Code, (ii) results in a "complete termination" of the holder's interest in all classes of our shares under Section 302(b)(3) of the Code, or (iii) is "not essentially equivalent to a dividend" with respect to the holder of the preferred shares under Section 302(b)(1) of the Code. In applying these tests, there must be taken into account not only the preferred shares being redeemed, but also such holder's ownership of other classes and series of our shares and any options (including stock purchase rights) to acquire any of the foregoing. The non-U.S. shareholder of our preferred shares also must take into account any such securities (including options) which are considered to be owned by such holder by reason of the constructive ownership rules set forth in Sections 318 and 302(c) of the Code.

        If the non-U.S. shareholder of preferred shares owns (actually or constructively) none of our voting shares, or owns an insubstantial amount of our voting shares, based upon current law, it is probable that the redemption of preferred shares from such a holder would be considered to be "not essentially equivalent to a dividend." However, whether a distribution is "not essentially equivalent to a dividend" depends on all of the facts and circumstances, and a non-U.S. shareholder of our preferred shares intending to rely on any of the tests in this or the preceding paragraph at the time of redemption should consult its tax advisor to determine their application to its particular situation. If the redemption does not meet any of the tests under Section 302 of the Code, then the redemption proceeds received from our preferred shares will be treated as a distribution on our shares as described under "Taxation of Shareholders—Taxation of Non-U.S. Shareholders—Taxation of Distributions." If the redemption of a holder's preferred shares is taxed as a dividend, the adjusted basis of such holder's redeemed preferred shares will be transferred to any other shares held by the holder. If the holder

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owns no other shares, under certain circumstances, such basis may be transferred to a related person, or it may be lost entirely.

        With respect to a redemption of our preferred shares that is treated as a distribution with respect to our shares, which is not otherwise taxable as a dividend, the IRS has proposed Treasury regulations that would require any basis reduction associated with such a redemption to be applied on a share-by-share basis which could result in taxable gain with respect to some shares, even though the holder's aggregate basis for the shares would be sufficient to absorb the entire amount of the redemption distribution (in excess of any amount of such distribution treated as a dividend). Additionally, these proposed Treasury regulations would not permit the transfer of basis in the redeemed shares of the preferred shares to the remaining shares held (directly or indirectly) by the redeemed holder. Instead, the unrecovered basis in our preferred shares would be treated as a deferred loss to be recognized when certain conditions are satisfied. These proposed Treasury regulations would be effective for transactions that occur after the date the regulations are published as final Treasury regulations. There can, however, be no assurance as to whether, when, and in what particular form such proposed Treasury regulations will ultimately be finalized.

        Conversion of Our Preferred Shares into Common Shares.    Except as provided below, a non-U.S. shareholder generally will not recognize gain or loss upon the conversion of our preferred shares into our common shares, provided our preferred shares do not constitute a USRPI. Even if our preferred shares do constitute a USRPI, provided our common shares also constitute a USRPI, a non-U.S. shareholder generally will not recognize gain or loss upon a conversion of our preferred shares into our common shares provided certain reporting requirements are satisfied. Except as provided below, a non-U.S. shareholder's basis and holding period in the common shares received upon conversion will be the same as those of the converted preferred shares (but the basis will be reduced by the portion of adjusted tax basis allocated to any fractional common share exchanged for cash). Any common shares received in a conversion that are attributable to accumulated and unpaid dividends on the converted preferred shares will be treated as a distribution on our shares as described under "—Taxation of Shareholders—Taxation of Non-U.S. Shareholders—Taxation of Distributions." Cash received upon conversion in lieu of a fractional common share generally will be treated as a payment in a taxable exchange for such fractional common share as described under "—Taxation of Shareholders—Taxation of Non-U.S. Shareholders—Taxation of Disposition of Shares." Non-U.S. shareholders should consult with their tax advisor regarding the U.S. federal income tax consequences of any transaction by which such holder exchanges common shares received on a conversion of preferred shares for cash or other property.

        Information Reporting and Backup Withholding Applicable to non-U.S. Shareholders.    CubeSmart must report annually to the IRS and to each non-U.S. shareholder the amount of dividends paid to such holder and the tax withheld with respect to such dividends, regardless of whether withholding was required. Copies of the information returns reporting such dividends and withholding may also be made available to the tax authorities in the country in which the non-U.S. shareholder resides under the provisions of an applicable income tax treaty.

        Payments of dividends or of proceeds from the disposition of shares made to a non-U.S. shareholder may be subject to information reporting and backup withholding unless such holder establishes an exemption, for example, by properly certifying its non-United States status on an IRS Form W-8 BEN or another appropriate version of IRS Form W-8. Notwithstanding the foregoing, backup withholding may apply if either CubeSmart or its paying agent has actual knowledge, or reason to know, that a non-U.S. shareholder is a United States person.

        Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules may be allowed as a refund or a credit against the shareholder's income tax liability, provided the required information is furnished to the IRS.

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Legislative or Other Actions Affecting REITs

        The rules dealing with U.S. federal income taxation are constantly under review by persons involved in the legislative process and by the IRS and the U.S. Treasury Department. No assurance can be given as to whether, when, or in what form, the U.S. federal income tax laws applicable to CubeSmart and its shareholders may be enacted. Changes to the U.S. federal tax laws and interpretations of U.S. federal tax laws could adversely affect an investment in CubeSmart shares.

Taxation of Holders of Debt Securities

        This section describes the material United States federal income tax consequences of owning the debt securities that the Operating Partnership may offer. This summary is for general information only and is not tax advice. The tax consequences of owning any particular issue of debt securities will be discussed in the applicable prospectus.

        As used herein, a "U.S. Holder" means a beneficial owner of debt securities of the Operating Partnership, who is, for U.S. federal income tax purposes:

        If a partnership holds debt securities, the tax treatment of a partner will generally depend upon the status of the partner and the activities of the partnership. If you are a partner of a partnership holding debt securities of the Operating Partnership, you should consult your tax advisor regarding the consequences of the ownership and disposition of debt securities by the partnership.

        Interest.    The stated interest on debt securities generally will be taxable to a U.S. Holder as ordinary income at the time that it is paid or accrued, in accordance with the U.S. Holder's method of accounting for United States federal income tax purposes.

        Original Issue Discount.    If you own debt securities issued with original issue discount ("OID"), you will be subject to special tax accounting rules, as described in greater detail below. In that case, you should be aware that you generally must include OID in gross income in advance of the receipt of cash attributable to that income. However, you generally will not be required to include separately in income cash payments received on the debt securities, even if denominated as interest, to the extent those payments do not constitute "qualified stated interest," as defined below. If we determine that a particular debt security will be an OID debt security, we will disclose that determination in the prospectus relating to those debt securities.

        A debt security with an "issue price" that is less than the "stated redemption price at maturity" (the sum of all payments to be made on the debt security other than "qualified stated interest") generally will be issued with OID if that difference is at least 0.25% of the stated redemption price at maturity multiplied by the number of complete years to maturity. The "issue price" of each debt security in a particular offering will be the first price at which a substantial amount of that particular

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offering is sold to the public. The term "qualified stated interest" means stated interest that is unconditionally payable in cash or in property, other than debt instruments of the issuer, and the interest to be paid meets all of the following conditions:

        If we determine that particular debt securities of a series will bear interest that is not qualified stated interest, we will disclose that determination in the prospectus relating to those debt securities.

        If you own a debt security issued with "de minimis" OID, which is discount that is not OID because it is less than 0.25% of the stated redemption price at maturity multiplied by the number of complete years to maturity, you generally must include the de minimis OID in income at the time principal payments on the debt securities are made in proportion to the amount paid. Any amount of de minimis OID that you have included in income will be treated as capital gain.

        Certain of the debt securities may contain provisions permitting them to be redeemed prior to their stated maturity at our option and/or at your option. OID debt securities containing those features may be subject to rules that differ from the general rules discussed herein. If you are considering the purchase of OID debt securities with those features, you should carefully examine the applicable prospectus and should consult your own tax advisors with respect to those features since the tax consequences to you with respect to OID will depend, in part, on the particular terms and features of the debt securities.

        If you own OID debt securities with a maturity upon issuance of more than one year you generally must include OID in income in advance of the receipt of some or all of the related cash payments using the "constant yield method" described in the following paragraphs. This method takes into account the compounding of interest.

        The amount of OID that you must include in income if you are the initial United States holder of an OID debt security is the sum of the "daily portions" of OID with respect to the debt security for each day during the taxable year or portion of the taxable year in which you held that debt security ("accrued OID"). The daily portion is determined by allocating to each day in any "accrual period" a pro rata portion of the OID allocable to that accrual period. The "accrual period" for an OID debt security may be of any length and may vary in length over the term of the debt security, provided that each accrual period is no longer than one year and each scheduled payment of principal or interest occurs on the first day or the final day of an accrual period. The amount of OID allocable to any accrual period is an amount equal to the excess, if any, of:

        OID allocable to a final accrual period is the difference between the amount payable at maturity, other than a payment of qualified stated interest, and the adjusted issue price at the beginning of the final accrual period. Special rules will apply for calculating OID for an initial short accrual period. The "adjusted issue price" of a debt security at the beginning of any accrual period is equal to its issue price increased by the accrued OID for each prior accrual period, determined without regard to the amortization of any acquisition or bond premium, as described below, and reduced by any payments made on the debt security (other than qualified stated interest) on or before the first day of the accrual

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period. Under these rules, you will generally have to include in income increasingly greater amounts of OID in successive accrual periods. We are required to provide information returns stating the amount of OID accrued on debt securities held of record by persons other than corporations and other exempt holders.

        Floating rate debt securities are subject to special OID rules. In the case of an OID debt security that is a floating rate debt security, both the "yield to maturity" and "qualified stated interest" will be determined solely for purposes of calculating the accrual of OID as though the debt security will bear interest in all periods at a fixed rate generally equal to the rate that would be applicable to interest payments on the debt security on its date of issue or, in the case of certain floating rate debt securities, the rate that reflects the yield to maturity that is reasonably expected for the debt security. Additional rules may apply if either:

        This discussion does not address the tax rules applicable to debt securities with an indexed principal amount. If you are considering the purchase of floating rate OID debt securities or securities with indexed principal amounts, you should carefully examine the prospectus relating to those debt securities, and should consult your own tax advisors regarding the United States federal income tax consequences to you of holding and disposing of those debt securities.

        You may elect to treat all interest on any debt securities as OID and calculate the amount includible in gross income under the constant yield method described above. For purposes of this election, interest includes stated interest, acquisition discount, OID, de minimis OID, market discount, de minimis market discount and unstated interest, as adjusted by any amortizable bond premium or acquisition premium. You must make this election for the taxable year in which you acquired the debt security, and you may not revoke the election without the consent of the IRS. You should consult with your own tax advisors about this election.

        Market Discount.    If you purchase debt securities, other than OID debt securities, after original issuance for an amount that is less than their stated redemption price at maturity, or, in the case of OID debt securities, their adjusted issue price, the amount of the difference will be treated as "market discount" for United States federal income tax purposes, unless that difference is less than a specified de minimis amount. Under the market discount rules, you will be required to treat any principal payment on, or any gain on the sale, exchange, retirement or other disposition of, the debt securities as ordinary income to the extent of the market discount that you have not previously included in income and are treated as having accrued on the debt securities at the time of their payment or disposition. In addition, you may be required to defer, until the maturity of the debt securities or their earlier disposition in a taxable transaction, the deduction of all or a portion of the interest expense on any indebtedness attributable to the debt securities. You may elect, on a debt security-by-debt security basis, to deduct the deferred interest expense in a tax year prior to the year of disposition. You should consult your own tax advisors before making this election.

        Any market discount will be considered to accrue ratably during the period from the date of acquisition to the maturity date of the debt securities, unless you elect to accrue on a constant interest method. You may elect to include market discount in income currently as it accrues, on either a ratable or constant interest method, in which case the rule described above regarding deferral of interest deductions will not apply. Your election to include market discount in income currently, once made, applies to all market discount obligations acquired by you on or after the first taxable year to which your election applies and may not be revoked without the consent of the IRS. You should consult your own tax advisor before making this election.

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        Acquisition Premium and Amortizable Bond Premium.    If you purchase OID debt securities for an amount that is greater than their adjusted issue price but equal to or less than the sum of all amounts payable on the debt securities after the purchase date other than payments of qualified stated interest, you will be considered to have purchased those debt securities at an "acquisition premium." Under the acquisition premium rules, the amount of OID that you must include in gross income with respect to those debt securities for any taxable year will be reduced by the portion of the acquisition premium properly allocable to that year.

        If you purchase debt securities (including OID debt securities) for an amount in excess of the sum of all amounts payable on those debt securities after the purchase date other than qualified stated interest, you will be considered to have purchased those debt securities at a "premium" and, if they are OID debt securities, you will not be required to include any OID in income. You generally may elect to amortize the premium over the remaining term of those debt securities on a constant yield method as an offset to interest when includible in income under your regular accounting method. In the case of debt securities that provide for alternative payment schedules, bond premium is calculated by assuming that (a) you will exercise or not exercise options in a manner that maximizes your yield, and (b) we will exercise or not exercise options in a manner that minimizes your yield (except that we will be assumed to exercise call options in a manner that maximizes your yield). If you do not elect to amortize bond premium, that premium will decrease the gain or increase the loss you would otherwise recognize on disposition of the debt security. Your election to amortize premium on a constant yield method will also apply to all debt obligations held or subsequently acquired by you on or after the first day of the first taxable year to which the election applies. You may not revoke the election without the consent of the IRS. You should consult your own tax advisor before making this election.

        Sale, Exchange and Retirement of Debt Securities.    A U.S. Holder of debt securities will recognize gain or loss upon the sale, exchange, retirement, redemption or other taxable disposition of such debt securities in an amount equal to the difference between:

        A U.S. Holder's adjusted tax basis in a debt security generally will equal the cost of the debt security to such holder (A) increased by the amount of OID or accrued market discount (if any) previously included in income by such holder and (B) decreased by the amount of (1) any payments other than qualified stated interest payments and (2) any amortizable bond premium taken by the holder.

        Any gain or loss recognized will generally be capital gain or loss, and such capital gain or loss will generally be long-term capital gain or loss if the debt security has been held by the U.S. Holder for more than one year. Long-term capital gain for non-corporate taxpayers is subject to reduced rates of United States federal income taxation (currently 20% maximum federal rate). The deductibility of capital losses is subject to certain limitations.

        If a U.S. Holder recognizes a loss upon a subsequent disposition of debt securities in an amount that exceeds a prescribed threshold, it is possible that the provisions of Treasury Regulations involving "reportable transactions" could apply, with a resulting requirement to separately disclose the loss generating transactions to the IRS. While these regulations are directed towards "tax shelters," they are written broadly, and apply to transactions that would not typically be considered tax shelters. Significant penalties apply for failure to comply with these requirements. You should consult your tax advisors concerning any possible disclosure obligation with respect to the receipt or disposition of debt securities, or transactions that might be undertaken directly or indirectly by us. Moreover, you should

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be aware that we and other participants in transactions involving us (including our advisors) might be subject to disclosure or other requirements pursuant to these regulations.

        Assuming the debt security is debt for tax purposes, interest income accrued on the debt security should not constitute unrelated business taxable income to a tax-exempt holder. As a result, a tax-exempt holder generally should not be subject to U.S. federal income tax on the interest income accruing on debt securities of the Operating Partnership. Similarly, any gain recognized by the tax-exempt holder in connection with a sale of the debt security generally should not be unrelated business taxable income. However, if a tax-exempt holder were to finance its acquisition of the debt security with debt, a portion of the interest income and gain attributable to the debt security would constitute unrelated business taxable income pursuant to the "debt-financed property" rules. Tax-exempt holders should consult their own counsel to determine the potential tax consequences of an investment in debt securities of the Operating Partnership.

        The term "non-U.S. Holder" means a beneficial owner of debt securities of the Operating Partnership that is not a U.S. Holder or a partnership (or an entity treated as a partnership for United States federal income tax purposes). The rules governing U.S. federal income taxation of non-U.S. Holders are complex. This section is only a summary of such rules. We urge non-U.S. Holders to consult their own tax advisors to determine the impact of federal, state, local and foreign income tax laws on ownership of debt securities, including any reporting requirements.

        Interest.    Interest (including OID) paid to a non-U.S. Holder of debt securities will not be subject to United States federal income or withholding tax under the "portfolio interest exception," provided that:

        A payment of interest (including OID) to a non-U.S. Holder that does not qualify for the portfolio interest exception and that is not effectively connected to a United States trade or business will be subject to United States federal withholding tax at a rate of 30%, unless a United States income tax treaty applies to reduce or eliminate withholding.

        A non-U.S. Holder will generally be subject to tax in the same manner as a U.S. Holder with respect to payments of interest (including OID) if such payments are effectively connected with the conduct of a trade or business by the non-U.S. Holder in the United States and, if an applicable tax treaty provides, such gain is attributable to a United States permanent establishment maintained by the

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non-U.S. Holder. In some circumstances, such effectively connected income received by a non-U.S. Holder which is a corporation may be subject to an additional "branch profits tax" at a 30% base rate or, if applicable, a lower treaty rate.

        To claim the benefit of a lower treaty rate or to claim exemption from withholding because the income is effectively connected with a United States trade or business, the non-U.S. Holder must provide a properly executed IRS Form W-8BEN or IRS Form W-8ECI, or a suitable substitute form, as applicable, prior to the payment of interest. Such certificate must contain, among other information, the name and address of the non-U.S. Holder.

        Non-U.S. Holders are urged to consult their own tax advisors regarding applicable income tax treaties, which may provide different rules.

        Sale or Retirement of Debt Securities.    A non-U.S. Holder generally will not be subject to United States federal income tax or withholding tax on gain realized on the sale, exchange or redemption of debt securities unless:

        Except to the extent that an applicable tax treaty provides otherwise, a non-U.S. Holder will generally be subject to tax in the same manner as a U.S. Holder with respect to gain realized on the sale, exchange or redemption of debt securities if such gain is effectively connected with the conduct of a trade or business by the non-U.S. Holder in the United States and, if an applicable tax treaty provides, such gain is attributable to a United States permanent establishment maintained by the non-U.S. Holder. In certain circumstances, a non-U.S. Holder that is a corporation will be subject to an additional "branch profits tax" at a 30% rate or, if applicable, a lower treaty rate on such income.

        U.S. Federal Estate Tax.    Your estate will not be subject to U.S. federal estate tax on the debt securities beneficially owned by you at the time of your death, provided that any payment to you on the debt securities, including OID, would be eligible for exemption from the 30% U.S. federal withholding tax under the "portfolio interest" rule described above, without regard to the certification requirement.

Information Reporting and Backup Withholding Applicable to Holders of Debt Securities

        Certain U.S. Holders may be subject to information reporting requirements on payments of principal and interest (including OID) on debt securities and payments of the proceeds of the sale, exchange, or redemption of debt securities, and backup withholding, currently imposed at a rate of 28%, may apply to such payment if the U.S. Holder:

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        A non-U.S. Holder is generally not subject to backup withholding with respect to payments of interest (including OID) on debt securities if it certifies as to its status as a non-U.S. Holder under penalties of perjury or if it otherwise establishes an exemption, provided that neither we nor our paying agent has actual knowledge or reason to know that the non-U.S. Holder is a United States person or that the conditions of any other exemptions are not, in fact, satisfied. Information reporting requirements, however, will apply to payments of interest (including OID) to non-U.S. Holders where such interest is subject to withholding or exempt from United States withholding tax pursuant to a tax treaty. Copies of these information returns may also be made available under the provisions of a specific treaty or agreement to the tax authorities of the country in which the non-U.S. Holder resides.

        The payment of the proceeds from the disposition of debt securities to or through the United States office of any broker, United States or foreign, will be subject to information reporting and possible backup withholding unless the owner certifies as to its non-United States status under penalties of perjury or otherwise establishes an exemption, provided that the broker does not have actual knowledge or reason to know that the non-U.S. Holder is a United States person or that the conditions of any other exemption are not, in fact, satisfied.

        The payment of the proceeds from the disposition of debt securities to or through a non-United States office of a non-United States broker that is not a "United States related person" generally will not be subject to information reporting or backup withholding. For this purpose, a "United States related person" is:

        In the case of the payment of proceeds from the disposition of debt securities to or through a non-United States office of a broker that is either a United States person or a United States related person, the payment may be subject to information reporting unless the broker has documentary evidence in its files that the owner is a non-U.S. Holder and the broker has no knowledge or reason to know to the contrary. Backup withholding will not apply to payments made through foreign offices of a broker that is a United States person or a United States related person, absent actual knowledge that the payee is a United States person.

        Backup withholding is not an additional tax. Any amounts withheld under the backup withholding rules from a payment to a Holder will be allowed as a refund or a credit against such Holder's United States federal income tax liability, provided that the requisite procedures are followed.

        Holders of debt securities are urged to consult their tax advisors regarding their qualification for exemption from backup withholding and the procedure for obtaining such an exemption, if applicable.

FATCA Withholding

        U.S. tax legislation ("FATCA") enacted in 2010 and subsequent IRS guidance provides that a 30% withholding tax will be imposed on payments of dividends on shares and interest on debt securities made after June 30, 2014 and payments of gross proceeds from the sale, exchange or other disposition of shares or debt securities made after December 31, 2016 to a foreign entity if such entity fails to

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satisfy certain new disclosure and reporting rules. In general, these new disclosure and reporting rules require that (i) in the case of a foreign financial entity, the entity identify and provide information in respect of financial accounts with such entity held (directly or indirectly) by U.S. persons and U.S.-owned foreign entities, and (ii) in the case of a non-financial foreign entity, the entity identify and provide information in respect of substantial U.S. owners of such entity. Additionally, various requirements and exceptions are provided under FATCA and additional or different requirements and exceptions may be provided in subsequent guidance. Prospective investors should consult their tax advisors regarding the possible implications of this legislation on their investment in common shares or preferred shares of CubeSmart or debt securities of the Operating Partnership.

Medicare Tax on Investment Income

        On March 30, 2010, the President signed into law the Health Care and Reconciliation Act of 2010 (the "Reconciliation Act"). The Reconciliation Act requires certain U.S. Shareholders and U.S. Holders who are individuals, estates or trusts and whose income exceeds certain thresholds to pay a 3.8% Medicare tax on "net investment income" which includes, among other things, dividends on shares, interest on debentures and capital gains from the sale or other disposition of shares or debentures, subject to certain exceptions. Prospective investors should consult their tax advisors regarding the effect, if any, of this legislation on their ownership and disposition of our common shares, preferred shares or debentures.

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PLAN OF DISTRIBUTION

        We may sell the securities from time to time in one or more transactions, including block transactions and transactions on the NYSE or on a delayed or continuous basis, in each case, through:

        The securities may be sold at a fixed price or prices, which may be changed, or at market prices prevailing at the time of sale, at prices relating to the prevailing market prices or at negotiated prices. The consideration may be cash or another form negotiated by the parties. Agents, underwriters or broker-dealers may be paid compensation for offering and selling the securities. That compensation may be in the form of discounts, concessions or commissions to be received from us or from the purchasers of the securities.

        For each offering of common shares, preferred shares, depositary shares, subscriptions rights, warrants or debt securities, the prospectus supplement or other offering materials will describe the specific plan, including:

        If we use underwriters for a sale of securities, the underwriters may offer and sell the securities at a fixed price or prices, which may be changed, or from time to time at market prices prevailing at the time of sale, at prices related to such prevailing market prices, at negotiated prices or under delayed delivery contracts or other contractual commitments. We also may, from time to time, authorize underwriters acting as agents to offer and sell the securities upon the terms and conditions set forth in any prospectus supplement. Underwriters may sell the securities to or through dealers, and such dealers may receive compensation in the form of discounts, concessions or commissions (which may be changed from time to time) from the underwriters and/or from the purchasers for whom they may act as agent.

        Offers to purchase the securities may be solicited by agents designated by us from time to time. Any such agent involved in the offer or sale of the securities will be named, and any commissions payable by the Company to such agent will be set forth in the prospectus supplement. Unless otherwise indicated in the prospectus supplement, any such agent will be acting on a best efforts basis for the period of its appointment. Any such agent may be deemed to be an underwriter, as that term is defined in the Securities Act, of the securities so offered and sold.

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        We may from time to time engage a firm to act as our agent for one or more offerings of our securities. We sometimes refer to this agent as our "offering agent." If we reach agreement with an offering agent with respect to a specific offering, including the number of securities and any minimum price below which sales may not be made, then the offering agent will try to sell such securities on the agreed terms. The offering agent could make sales in privately negotiated transactions and/or any other method permitted by law, including sales deemed to be an "at-the-market" offering as defined in Rule 415 promulgated under the Securities Act, including sales made directly on the NYSE, or sales made to or through a market maker other than on an exchange. The offering agent will be deemed to be an "underwriter" within the meaning of the Securities Act with respect to any sales effected through an "at-the-market" offering.

        If an underwriter or underwriters are utilized in the sale of securities, we will execute an underwriting agreement with such underwriter or underwriters at the time an agreement for such sale is reached, and the names of the specific managing underwriter or underwriters, as well as any other underwriters, and the terms of the transactions, including compensation of the underwriters and dealers, if any, will be set forth in the prospectus supplement, which will be used by the underwriters to resell the securities.

        If a dealer is utilized in the sale of the securities, we will sell such securities to the dealer, as principal. The dealer may then resell such securities to the public at varying prices to be determined by such dealer at the time of resale. The name of the dealer and the terms of the transactions will be set forth in the prospectus supplement relating thereto.

        Offers to purchase the securities may be solicited directly by us and sales thereof may be made by us directly to institutional investors or others. The terms of any such sales, including the terms of any bidding or auction prices, if utilized, will be described in the prospectus supplement relating thereto.

        Some or all of the securities that we offer through this prospectus may be new issues of securities with no established trading market. Any underwriters to whom we sell securities for public offering and sale may make a market in those securities, but they will not be obligated to and they may discontinue any market making at any time without notice. Accordingly, we cannot assure you of the liquidity of, or continued trading markets for, any securities offered pursuant to this prospectus. If we use dealers in the sale, we will sell securities to those dealers as principals. The dealers may then resell the securities to the public at any market price or other prices to be determined by the dealers at the time of resale. If we use agents in the sale, unless we inform you otherwise in the prospectus supplement or other applicable offering materials, they will use their reasonable best efforts to solicit purchasers for the period of their appointment. If we sell directly, no underwriters or agents would be involved. In the prospectus supplement or other applicable offering materials, we will name any agent involved in the offer or sale of the offered securities, and we will describe any commissions payable to the agent. We are not making an offer of securities in any state that does not permit such an offer.

        If indicated in the applicable prospectus supplement, we may authorize underwriters or other persons acting as our agents to solicit offers by institutions or other suitable purchasers to purchase the securities from us at the public offering price set forth in the prospectus supplement, pursuant to delayed delivery contracts providing for payment and delivery on the date or dates stated in the prospectus supplement. These purchasers may include, among others, commercial and savings banks, insurance companies, pension funds, investment companies, educational and charitable institutions and other institutions, but will in all cases be subject to our approval. Delayed delivery contracts will be subject to the condition that the purchase of the securities covered by the delayed delivery contracts will not at the time of delivery be prohibited under the laws of any jurisdiction in the United States to which the purchaser is subject. The underwriters and agents will not have any responsibility with respect to the validity or performance of these contracts.

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        To facilitate the offering of the securities, certain persons participating in the offering may engage in transactions that stabilize, maintain, or otherwise affect the price of the securities. This may include over-allotments or short sales of the securities, which involves the sale by persons participating in the offering of more securities than we sold to them. In these circumstances, these persons would cover the over-allotments or short positions by making purchases in the open market or by exercising their over-allotment option. In addition, these persons may stabilize or maintain the price of the securities by bidding for or purchasing securities in the open market or by imposing penalty bids, whereby selling concessions allowed to dealers participating in the offering may be reclaimed if securities sold by them are repurchased in connection with stabilization transactions. The effect of these transactions may be to stabilize or maintain the market price of the securities at a level above that which might otherwise prevail in the open market. These transactions may be discontinued at any time.

        Underwriters, dealers and agents participating in the distribution of the securities may be deemed to be underwriters, and any discounts and commissions received by them from us or from purchasers of the securities and any profit realized by them on resale of the securities may be deemed to be underwriting discounts and commissions under the Securities Act. If such dealers or agents were deemed to be underwriters, they may be subject to statutory liabilities under the Securities Act. Underwriters, dealers and agents may be entitled, under agreements entered into with us, to indemnification against and contribution toward certain civil liabilities, including liabilities under the Securities Act.

        In the ordinary course of business, we may engage in transactions with underwriters, dealers, agents and their affiliates and they may perform services for us.

LEGAL MATTERS

        Unless otherwise set forth in a prospectus supplement, the validity of the securities offered will be passed upon for us by Pepper Hamilton LLP.

EXPERTS

        The consolidated financial statements and financial statement schedule of CubeSmart as of December 31, 2013 and 2012 and for each of the years in the three-year period ended December 31, 2013 and management's assessment of the effectiveness of internal control over financial reporting as of December 31, 2013 have been incorporated by reference herein in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

        The consolidated financial statements and financial statement schedule of CubeSmart, L.P. as of December 31, 2013 and 2012 and for each of the years in the three-year period ended December 31, 2013 and management's assessment of effectiveness of internal control over financial reporting as of December 31, 2013 have been incorporated by reference herein in reliance upon the reports of KPMG LLP, independent registered public accounting firm, incorporated by reference herein, and upon the authority of said firm as experts in accounting and auditing.

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October      , 2014