    <SEC-DOCUMENT>0001104659-21-044379-index.html : 20210331
    <SEC-HEADER>0001104659-21-044379.hdr.sgml : 20210331
    <ACCEPTANCE-DATETIME>20210331083114
    ACCESSION NUMBER:		0001104659-21-044379
    CONFORMED SUBMISSION TYPE:	DEFA14A
    PUBLIC DOCUMENT COUNT:		5
    FILED AS OF DATE:		20210331
    DATE AS OF CHANGE:		20210331

    FILER:

    	COMPANY DATA:
    		COMPANY CONFORMED NAME:			CubeSmart
    		CENTRAL INDEX KEY:			0001298675
    		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
    		IRS NUMBER:				201024732
    		STATE OF INCORPORATION:			MD
    		FISCAL YEAR END:			1231

    	FILING VALUES:
    		FORM TYPE:		DEFA14A
    		SEC ACT:		1934 Act
    		SEC FILE NUMBER:	001-32324
    		FILM NUMBER:		21789961

    	BUSINESS ADDRESS:
    		STREET 1:		5 OLD LANCASTER ROAD
    		CITY:			MALVERN
    		STATE:			PA
    		ZIP:			19355
    		BUSINESS PHONE:		610-535-5700

    	MAIL ADDRESS:
    		STREET 1:		5 OLD LANCASTER ROAD
    		CITY:			MALVERN
    		STATE:			PA
    		ZIP:			19355

    	FORMER COMPANY:
    		FORMER CONFORMED NAME:	U-Store-It Trust
    		DATE OF NAME CHANGE:	20040727
    </SEC-HEADER>
    <DOCUMENT>
    <TYPE>DEFA14A
    <SEQUENCE>1
    <FILENAME>tm212390d2_defa14a.htm
    <DESCRIPTION>DEFA14A
    <TEXT>
    Document 1 - file: tm212390d2_defa14a.htm

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>2
    <FILENAME>tm212390d2_defa14aimg001.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 2 - file: tm212390d2_defa14aimg001.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>3
    <FILENAME>tm212390d2_defa14aimg002.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 3 - file: tm212390d2_defa14aimg002.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>4
    <FILENAME>tm212390d2_defa14aimg003.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 4 - file: tm212390d2_defa14aimg003.jpg

    </DOCUMENT>
    <DOCUMENT>
    <TYPE>GRAPHIC
    <SEQUENCE>5
    <FILENAME>tm212390d2_defa14aimg004.jpg
    <DESCRIPTION>GRAPHIC
    <TEXT>
    Document 5 - file: tm212390d2_defa14aimg004.jpg

    </DOCUMENT>
    </SEC-DOCUMENT>