-----BEGIN PRIVACY-ENHANCED MESSAGE-----
Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
Originator-Key-Asymmetric:
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 ISEvKAF2RkyK4Va+INrcWwKDBFaUcu/5Ro5jG7wNgC7Xn4sVvTvEhgzxEdlkc1Wt
 HnbePUepbgC56TGtT3s5cA==

<SEC-DOCUMENT>0001024193-04-000007.txt : 20041214
<SEC-HEADER>0001024193-04-000007.hdr.sgml : 20041214
<ACCEPTANCE-DATETIME>20041214120408
ACCESSION NUMBER:		0001024193-04-000007
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20041210
FILED AS OF DATE:		20041214
DATE AS OF CHANGE:		20041214

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:		2 N RIVERSIDE PLAZA, STE 400
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3129281178

	MAIL ADDRESS:	
		STREET 1:		TWO N RIVERSIDE PLAZA
		STREET 2:		SUITE 450
		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:			ZELL SAMUEL
		CENTRAL INDEX KEY:			0001024193

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-12252
		FILM NUMBER:		041200675

	BUSINESS ADDRESS:	
		STREET 1:		TWO N RIVERSIDE PLAZA SUITE 600
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
		BUSINESS PHONE:		3124540100

	MAIL ADDRESS:	
		STREET 1:		TWO N RIVERSIDE PLAZA
		STREET 2:		SUITE 600
		CITY:			CHICAGO
		STATE:			IL
		ZIP:			60606
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>c0001024193d20041214f4p2f.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2004-12-10</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001024193</rptOwnerCik>
            <rptOwnerName>ZELL SAMUEL</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>TWO NORTH RIVERSIDE PLAZA</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 600</rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60606</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle></officerTitle>
            <otherText>Chairman of the Board</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Operating Partnership Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>0</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2004-12-10</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>C</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F8"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1246</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>35.88</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2004-12-10</value>
            </exerciseDate>
            <expirationDate>
                <value>2014-12-10</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Shares of Beneficial Interest</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1246</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>SZ Matthew Trust</value>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F8">On December 10, 2004 the Units reported on this line were converted into Shares on a one-for-one basis and assigned to the SZ Matthew Trust (&quot;SZMT&quot;) at the closing market price of $35.88 per share. Shares reported herein are beneficially owned by  SZMT, of which Chai Trust is the sole Trustee. Mr. Zell is not an officer or director of Chai Trust and does not have voting or dispositive power over such shares. Mr. Zell is beneficiary of the SZMT and, as such, Mr. Zell may be deemed the beneficial owner of the shares reported herein.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>Samuel  Zell</signatureName>
        <signatureDate>2004-12-14</signatureDate>
    </ownerSignature>
</ownershipDocument>

</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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