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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
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<SEC-DOCUMENT>0001140361-09-016054.txt : 20090707
<SEC-HEADER>0001140361-09-016054.hdr.sgml : 20090707
<ACCEPTANCE-DATETIME>20090707164053
ACCESSION NUMBER:		0001140361-09-016054
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20090701
FILED AS OF DATE:		20090707
DATE AS OF CHANGE:		20090707

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Elliott Kelley
		CENTRAL INDEX KEY:			0001347672

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20199
		FILM NUMBER:		09933637

	MAIL ADDRESS:	
		STREET 1:		13900 RIVERPORT DRIVE
		CITY:			MARYLAND HEIGHTS
		STATE:			MO
		ZIP:			63043

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			EXPRESS SCRIPTS INC
		CENTRAL INDEX KEY:			0000885721
		STANDARD INDUSTRIAL CLASSIFICATION:	RETAIL-DRUG STORES AND PROPRIETARY STORES [5912]
		IRS NUMBER:				431420563
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		ONE EXPRESS WAY
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63121
		BUSINESS PHONE:		3149960900

	MAIL ADDRESS:	
		STREET 1:		ONE EXPRESS WAY
		CITY:			ST LOUIS
		STATE:			MO
		ZIP:			63121
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2009-07-01</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000885721</issuerCik>
        <issuerName>EXPRESS SCRIPTS INC</issuerName>
        <issuerTradingSymbol>ESRX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001347672</rptOwnerCik>
            <rptOwnerName>Elliott Kelley</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O EXPRESS SCRIPTS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>ONE EXPRESS WAY</rptOwnerStreet2>
            <rptOwnerCity>ST. LOUIS</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>63121</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Accounting Officer</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Stock Unit</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F2"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2009-07-01</value>
            </transactionDate>
            <deemedExecutionDate>
                <value>2009-07-02</value>
            </deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>9.0373</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>68.07</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Express Scripts, Inc. Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>9.0373</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>537.7243</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Phantom Stock Unit credited under Express Scripts, Inc. Executive Deferred Compensation Plan.</footnote>
        <footnote id="F2">Upon distribution each phantom stock unit converts to one share of Express Scripts, Inc. Common Stock.</footnote>
        <footnote id="F3">Voluntary contribution by participant in the Executive Deferred Compensation Plan; shares are 100% vested at time of contribution.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Kelley Elliott</signatureName>
        <signatureDate>2009-07-07</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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