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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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MIC-Info: RSA-MD5,RSA,
 EsoB7PUBOj4qlEg7025GybCaJfIEOl4hzY9TOE8ogoSQMUCQujIoVPzbRj1iTwVv
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<SEC-DOCUMENT>0001140361-07-004908.txt : 20070302
<SEC-HEADER>0001140361-07-004908.hdr.sgml : 20070302
<ACCEPTANCE-DATETIME>20070302165726
ACCESSION NUMBER:		0001140361-07-004908
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20070228
FILED AS OF DATE:		20070302
DATE AS OF CHANGE:		20070302

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:		13900 REIVERPORT DRIVE
		CITY:			MARYLAND HEIGHTS
		STATE:			MO
		ZIP:			63043
		BUSINESS PHONE:		3147701666

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

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			STIFTEN EDWARD J
		CENTRAL INDEX KEY:			0001285538

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-20199
		FILM NUMBER:		07668511

	MAIL ADDRESS:	
		STREET 1:		13900 RIVERPORT DRIVE
		CITY:			MARYLAND HEIGHT
		STATE:			MO
		ZIP:			63043
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>doc1.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0202</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2007-02-28</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001285538</rptOwnerCik>
            <rptOwnerName>STIFTEN EDWARD J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O EXPRESS SCRIPTS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>13900 RIVERPORT DRIVE</rptOwnerStreet2>
            <rptOwnerCity>MARYLAND HEIGHTS</rptOwnerCity>
            <rptOwnerState>MO</rptOwnerState>
            <rptOwnerZipCode>63043</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Sr Vice President &amp;  CFO</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2007-02-28</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>622</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>75.41</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>46095</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value></value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents shares tendered to Express Scripts, Inc. to cover Mr. Stiften?s tax liability due upon lapse of restrictions of restricted stock previously awarded under Express Scripts, Inc. 2000 Long Term Incentive Plan.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Edward J. Stiften</signatureName>
        <signatureDate>2007-03-02</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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