-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 TqFNJgUI1CgGPrriqVXtaXpcqFfpTFuVs6l1IgzK/uiFC8nsvpH/7IyLOKYUcfTM
 hsIpTTuE/+F9Nx4CawaSmw==

<SEC-DOCUMENT>0000906107-08-000051.txt : 20080603
<SEC-HEADER>0000906107-08-000051.hdr.sgml : 20080603
<ACCEPTANCE-DATETIME>20080603101940
ACCESSION NUMBER:		0000906107-08-000051
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20080602
FILED AS OF DATE:		20080603
DATE AS OF CHANGE:		20080603

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EQUITY RESIDENTIAL
		CENTRAL INDEX KEY:			0000906107
		STANDARD INDUSTRIAL CLASSIFICATION:	REAL ESTATE INVESTMENT TRUSTS [6798]
		IRS NUMBER:				363877868
		STATE OF INCORPORATION:			MD
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		EQUITY RESIDENTIAL
		STREET 2:		TWO NORTH RIVERSIDE PLAZA, SUITE 400
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3129281178

	MAIL ADDRESS:	
		STREET 1:		TWO NORTH RIVERSIDE PLAZA
		STREET 2:		SUITE 400
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	EQUITY RESIDENTIAL PROPERTIES TRUST
		DATE OF NAME CHANGE:	19930524

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			KNOX BOONE A
		CENTRAL INDEX KEY:			0001028578

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12252
		FILM NUMBER:		08876119

	BUSINESS ADDRESS:	
		STREET 1:		149 MAIN ST
		STREET 2:		PO BOX 26
		CITY:			THOMSON
		STATE:			GA
		ZIP:			30825
		BUSINESS PHONE:		(706) 595-1907

	MAIL ADDRESS:	
		STREET 1:		C/O THE KNOX FOUNDATION/KNOX, LTD.
		STREET 2:		3133 WASHINGTON ROAD, N.W.
		CITY:			THOMSON
		STATE:			GA
		ZIP:			30824
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2008-06-02</periodOfReport>

    <issuer>
        <issuerCik>0000906107</issuerCik>
        <issuerName>EQUITY RESIDENTIAL</issuerName>
        <issuerTradingSymbol>EQR</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001028578</rptOwnerCik>
            <rptOwnerName>KNOX BOONE A</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>THE KNOX FOUNDATION / KNOX, LTD.</rptOwnerStreet1>
            <rptOwnerStreet2>3133 WASHINGTON ROAD, N.W.</rptOwnerStreet2>
            <rptOwnerCity>THOMSON</rptOwnerCity>
            <rptOwnerState>GA</rptOwnerState>
            <rptOwnerZipCode>30824</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>238538.0989</value>
                    <footnoteId id="F1"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>335892</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Folkstone</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>359678</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Knox Foundation</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2347898</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Knox, Ltd.</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <transactionDate>
                <value>2008-06-02</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1136</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>41.92</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>15055.8003</value>
                    <footnoteId id="F5"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>SERP Account</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>144298</value>
                    <footnoteId id="F6"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Sister-In-Law</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Shares of Beneficial Interest</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6228</value>
                    <footnoteId id="F7"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Spouse</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">Direct total includes restricted shares of the Company scheduled to vest in the future.</footnote>
        <footnote id="F2">Shares reported herein are beneficially owned by Folkstone Limited Partnership (FLP). Mr. Knox is a general partner of FLP. Mr. Knox disclaims beneficial ownership of the shares owned by FLP except to the extent of his pecuniary interest therein.</footnote>
        <footnote id="F4">Shares reported herein are beneficially owned by Knox, Ltd.. Mr. Knox is the general partner of Knox, Ltd.. Mr. Knox disclaims beneficial ownership of the shares owned by Knox, Ltd. except to the extent of his pecuniary interest therein.</footnote>
        <footnote id="F7">Shares reported herein are beneficially owned by Mr. Knox's spouse.  Mr. Knox disclaims beneficial ownership of these shares and this report shall not be deemed an admission that Mr. Knox is the beneficial owner of such shares for purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F3">Shares reported herein are beneficially owned by the Knox Foundation, a charitable trust. Mr. Knox is trustee of the Knox Foundation. Mr. Knox disclaims beneficial ownership of these shares and this report shall not be deemed an admission that Mr. Knox is the beneficial owner of such shares for purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F5">Represents shares owned by AST Trust Company, as Trustee of the Equity Residential Supplemental Executive Retirement Plan, for the benefit of the reporting person.</footnote>
        <footnote id="F6">Shares reported herein are beneficially owned by Mr. Knox's sister-in-law, over which he has investment authority.  Mr. Knox disclaims beneficial ownership of these shares and this report shall not be deemed an admission that Mr. Knox is the beneficial owner of such shares for purposes of Section 16 or any other purpose.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>By: Yasmina Duwe, Attorney-in-fact</signatureName>
        <signatureDate>2008-06-03</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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