-----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,
 OImsnzCNJak9QKXKbnsj19chpJSVFRc7Cll8qQZbJtIdU7ZFWYVXTx8Bismzi7Kf
 OYhLF8s4EoAhDPgLEHzyuQ==

<SEC-DOCUMENT>0001234902-03-000001.txt : 20030623
<SEC-HEADER>0001234902-03-000001.hdr.sgml : 20030623
<ACCEPTANCE-DATETIME>20030623123557
ACCESSION NUMBER:		0001234902-03-000001
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20030620
FILED AS OF DATE:		20030623

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			DWIGHT CRAIG M
		CENTRAL INDEX KEY:			0001234902

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-10792
		FILM NUMBER:		03752909

	MAIL ADDRESS:	
		STREET 1:		515 FRANKLIN SQ
		CITY:			MICHIGAN CITY
		STATE:			IN
		ZIP:			46360

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HORIZON BANCORP /IN/
		CENTRAL INDEX KEY:			0000706129
		STANDARD INDUSTRIAL CLASSIFICATION:	STATE COMMERCIAL BANKS [6022]
		IRS NUMBER:				351562417
		STATE OF INCORPORATION:			IN
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		515 FRANKLIN SQ
		CITY:			MICHIGAN CITY
		STATE:			IN
		ZIP:			46360
		BUSINESS PHONE:		2198790211

	MAIL ADDRESS:	
		STREET 1:		515 FRANKLIN SQ
		CITY:			MICHIGAN CITY
		STATE:			IN
		ZIP:			46360

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CITIZENS MICHIANA FINANCIAL CORP
		DATE OF NAME CHANGE:	19861021
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>

<ownershipDocument>

    <documentType>4</documentType>

    <periodOfReport>2003-06-20</periodOfReport>


    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000706129</issuerCik>
        <issuerName>HORIZON BANCORP /IN/</issuerName>
        <issuerTradingSymbol>hbnc</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001234902</rptOwnerCik>
            <rptOwnerName>DWIGHT CRAIG M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>  </rptOwnerStreet1>
            <rptOwnerStreet2>  </rptOwnerStreet2>
            <rptOwnerCity>  </rptOwnerCity>
            <rptOwnerState>  </rptOwnerState>
            <rptOwnerZipCode>  </rptOwnerZipCode>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>CEO</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeSecurity>
        <securityTitle>
            <value>common stock</value>
        </securityTitle>
        <transactionDate>
            <value>2003-06-20</value>
        </transactionDate>
        <transactionCoding>
            <transactionFormType>4</transactionFormType>
            <transactionCode>M</transactionCode>
            <equitySwapInvolved>0</equitySwapInvolved>
        </transactionCoding>
        <transactionTimeliness>
            <value></value>
        </transactionTimeliness>
        <transactionAmounts>
            <transactionShares>
                <value>3600</value>
            </transactionShares>
            <transactionValue>
                <value>31.28</value>
            </transactionValue>
            <transactionAcquiredDisposedCode>
                <value>A</value>
            </transactionAcquiredDisposedCode>
        </transactionAmounts>
        <postTransactionAmounts>
            <sharesOwnedFollowingTransaction>
                <value>3600</value>
            </sharesOwnedFollowingTransaction>
        </postTransactionAmounts>
        <ownershipNature>
            <directOrIndirectOwnership>
                <value>D</value>
            </directOrIndirectOwnership>
        </ownershipNature>
    </nonDerivativeSecurity>

    <derivativeSecurity>
        <securityTitle>
            <value>Employee Stock Options Rights to buy</value>
        </securityTitle>
        <conversionOrExercisePrice>
            <value>31.28</value>
        </conversionOrExercisePrice>
        <transactionDate>
            <value>2003-06-20</value>
        </transactionDate>
        <transactionCoding>
            <transactionFormType>4</transactionFormType>
            <transactionCode>M</transactionCode>
            <equitySwapInvolved>0</equitySwapInvolved>
        </transactionCoding>
        <transactionTimeliness>
            <value></value>
        </transactionTimeliness>
        <transactionAmounts>
            <transactionShares>
                <value>3600</value>
            </transactionShares>
            <transactionValue>
                <value>0</value>
            </transactionValue>
            <transactionAcquiredDisposedCode>
                <value>D</value>
            </transactionAcquiredDisposedCode>
        </transactionAmounts>
        <exerciseDate>
            <value>1988-08-08</value>
            <footnoteId id="F1"/>
            <footnoteId id="F2"/>
        </exerciseDate>
        <expirationDate>
            <value>2011-01-28</value>
        </expirationDate>
        <underlyingSecurity>
            <underlyingSecurityTitle>
                <value>Common stock</value>
            </underlyingSecurityTitle>
            <underlyingSecurityShares>
                <value>3600</value>
            </underlyingSecurityShares>
        </underlyingSecurity>
        <postTransactionAmounts>
            <sharesOwnedFollowingTransaction>
                <value>0</value>
            </sharesOwnedFollowingTransaction>
        </postTransactionAmounts>
        <ownershipNature>
            <directOrIndirectOwnership>
                <value>D</value>
            </directOrIndirectOwnership>
        </ownershipNature>
    </derivativeSecurity>

    <footnotes>
        <footnote id="F1">He also indirectly owns 12,629 shares held in stock bonus plan</footnote>
        <footnote id="F2">The options become exercisable in cumulative 20% increments on the anniversay of their date of grant in each of the five years following grant.</footnote>
    </footnotes>

    <ownerSignature>
        <signatureName>/s/Craig M. Dwight</signatureName>
        <signatureDate>2003-06-23</signatureDate>
    </ownerSignature>

</ownershipDocument>

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