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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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 G5V6VJJyIMTKUjnU8Y02eA==

<SEC-DOCUMENT>0001042046-03-000232.txt : 20031215
<SEC-HEADER>0001042046-03-000232.hdr.sgml : 20031215
<ACCEPTANCE-DATETIME>20031215104304
ACCESSION NUMBER:		0001042046-03-000232
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20031212
FILED AS OF DATE:		20031215

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			INFINITY PROPERTY & CASUALTY CORP
		CENTRAL INDEX KEY:			0001195933
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				030483872
		STATE OF INCORPORATION:			OH

	BUSINESS ADDRESS:	
		STREET 1:		2204 LAKESHORE DRIVE
		STREET 2:		SUITE 125
		CITY:			BIRMINGHAM
		STATE:			AL
		ZIP:			35209
		BUSINESS PHONE:		205-870-4000

	MAIL ADDRESS:	
		STREET 1:		2204 LAKESHORE DRIVE
		STREET 2:		SUITE 125
		CITY:			BIRMINGHAM
		STATE:			AL
		ZIP:			35209

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			AMERICAN FINANCIAL GROUP INC
		CENTRAL INDEX KEY:			0001042046
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		STATE OF INCORPORATION:			OH
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-50167
		FILM NUMBER:		031053299

	BUSINESS ADDRESS:	
		STREET 1:		ONE EAST FOURTH STREET
		STREET 2:		SUITE 919
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45202
		BUSINESS PHONE:		5135792121

	MAIL ADDRESS:	
		STREET 1:		ONE EAST FOURTH STREET
		STREET 2:		SUITE 919
		CITY:			CINCINNATI
		STATE:			OH
		ZIP:			45202

	FORMER NAME:	
		FORMER CONFORMED NAME:	AMERICAN FINANCIAL GROUP HOLDINGS INC
		DATE OF NAME CHANGE:	19970709
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2003-12-12</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001195933</issuerCik>
        <issuerName>INFINITY PROPERTY &amp; CASUALTY CORP</issuerName>
        <issuerTradingSymbol>IPCC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001042046</rptOwnerCik>
            <rptOwnerName>AMERICAN FINANCIAL GROUP INC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>ONE EAST FOURTH STREET</rptOwnerStreet1>
            <rptOwnerStreet2>SUITE 919</rptOwnerStreet2>
            <rptOwnerCity>CINCINNATI</rptOwnerCity>
            <rptOwnerState>OH</rptOwnerState>
            <rptOwnerZipCode>45202</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>

        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2003-12-12</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>7850465</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>30.5</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>#1</value>
                    <footnoteId id="F1"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>

    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Indirect #1:  American Premier Underwriters, 100% owned subsidiary of American financial Group, Inc.</footnote>
    </footnotes>


    <ownerSignature>
        <signatureName>Karl J. Grafe, Secretary</signatureName>
        <signatureDate>2003-12-15</signatureDate>
    </ownerSignature>

</ownershipDocument>

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