<?xml version="1.0"?><ownershipDocument>
    <schemaVersion>X0201</schemaVersion>

    <documentType>4</documentType><periodOfReport>2003-12-31</periodOfReport><notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000075129</issuerCik>
        <issuerName>OTTER TAIL CORP</issuerName>
        <issuerTradingSymbol>OTTR</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001191495</rptOwnerCik>
            <rptOwnerName>BROWN THOMAS M</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>215 S CASCADE ST</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>FERGUS FALLS</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>56537-2801</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>2003-12-31</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>A</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>124.0000</value></transactionShares><transactionPricePerShare><value>27.1550</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>A</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>6022.0000</value><footnoteId id="F1" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><footnotes><footnote id="F1">These shares of Common Stock were acquired under the 1999 Stock Incentive Plan at fair market value as part of the Compensation Program for Outside Directors:  1,000 shares of this total are held in "street name" through Piper Jaffray.  2,050 shares of this total are a grant of Restricted Stock.  250 shares of this total no longer carries the restriction.  See below for other holdings:
1.  2,000 stock options with expiration date of 4/9/2010.
2.  2,000 stock options with expiration date of 4/8/2011.
</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>/s/ Thomas M Brown by Debra J Lill - POA</signatureName><signatureDate>2004-01-02</signatureDate></ownerSignature></ownershipDocument>

