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Proc-Type: 2001,MIC-CLEAR
Originator-Name: webmaster@www.sec.gov
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 TWSM7vrzLADbmYQaionwg5sDW3P6oaM5D3tdezXMm7z1T+B+twIDAQAB
MIC-Info: RSA-MD5,RSA,
 UXUaECynoYNfDGrAMIe26sLS4Uh7BaZ104zS1MC8w6wV5KNxFcK8I28ugB19dZ6l
 OPnRbuZStQmM+zTywpV0HA==

<SEC-DOCUMENT>0001137688-10-000002.txt : 20100210
<SEC-HEADER>0001137688-10-000002.hdr.sgml : 20100210
<ACCEPTANCE-DATETIME>20100210120336
ACCESSION NUMBER:		0001137688-10-000002
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20100208
FILED AS OF DATE:		20100210
DATE AS OF CHANGE:		20100210

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			HORIZON BANCORP /IN/
		CENTRAL INDEX KEY:			0000706129
		STANDARD INDUSTRIAL CLASSIFICATION:	NATIONAL COMMERCIAL BANKS [6021]
		IRS NUMBER:				351562417
		STATE OF INCORPORATION:			IN
		FISCAL YEAR END:			1231

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

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

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	CITIZENS MICHIANA FINANCIAL CORP
		DATE OF NAME CHANGE:	19861021

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			PAIRITZ PETER L
		CENTRAL INDEX KEY:			0001137688

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-10792
		FILM NUMBER:		10586860

	MAIL ADDRESS:	
		STREET 1:		3171 N 525 W
		CITY:			LAPORTE
		STATE:			IN
		ZIP:			46350
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>primary_doc.xml
<DESCRIPTION>PRIMARY DOCUMENT
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0303</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-02-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001137688</rptOwnerCik>
            <rptOwnerName>PAIRITZ PETER L</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>3171 N 525 W</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>LAPORTE</rptOwnerCity>
            <rptOwnerState>IN</rptOwnerState>
            <rptOwnerZipCode>46350</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2010-02-08</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>522</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>19.15</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7201</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>13750</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Profit Sharing</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <ownerSignature>
        <signatureName>/s/ Mark E. Secor, Attorney-in-Fact</signatureName>
        <signatureDate>2010-02-10</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
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