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

    <documentType>4</documentType><periodOfReport>2003-12-17</periodOfReport><notSubjectToSection16>0</notSubjectToSection16>
    <issuer>
        <issuerCik>0000075129</issuerCik>
        <issuerName>OTTER TAIL CORP</issuerName>
        <issuerTradingSymbol>OTTR</issuerTradingSymbol></issuer><reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001191494</rptOwnerCik>
            <rptOwnerName>MACFARLANE JOHN C</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>2003-12-17</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>G</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>92.0000</value></transactionShares><transactionPricePerShare><value>27.1000</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>2678.0000</value></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></nonDerivativeTransaction><nonDerivativeTransaction><securityTitle><value>Common Stock</value></securityTitle><transactionDate><value>2003-12-22</value></transactionDate><deemedExecutionDate></deemedExecutionDate><transactionCoding><transactionFormType>4</transactionFormType><transactionCode>G</transactionCode><equitySwapInvolved>0</equitySwapInvolved></transactionCoding><transactionTimeliness><value></value></transactionTimeliness><transactionAmounts><transactionShares><value>38.0000</value></transactionShares><transactionPricePerShare><value>27.1000</value></transactionPricePerShare><transactionAcquiredDisposedCode><value>D</value></transactionAcquiredDisposedCode></transactionAmounts><postTransactionAmounts><sharesOwnedFollowingTransaction><value>2640.0000</value><footnoteId id="F1" /></sharesOwnedFollowingTransaction></postTransactionAmounts><ownershipNature><directOrIndirectOwnership><value>D</value></directOrIndirectOwnership></ownershipNature></nonDerivativeTransaction></nonDerivativeTable><footnotes><footnote id="F1">These shares are held jointly with his wife.  See below for other holdings:
1.  Indirect holding of 18,301.6644 shares held by ESOP.
2.  Indirect holding of 3,110.2390 shares by IRA.
3.  Direct holding of 20,928.0096 shares held in Dividend Reinvestment Plan.
4.  Direct holding of 2,142.5914 shares held in Employee Stock Purchase Plan.
5.  Direct holding of 4,550 shares which is a grant of Restricted Stock.
6.  Direct holding of 5,174 shares which no longer carries the restriction.
7.  52,000 stock options with expiration date of 2/22/2009.
8.  100,000 stock options with expiration date of 4/9/2010.
9.  100,000 stock options with expiration date of 4/8/2011.</footnote></footnotes><remarks></remarks><ownerSignature><signatureName>/s/ John C MacFarlane by Debra J Lill - POA</signatureName><signatureDate>2004-01-02</signatureDate></ownerSignature></ownershipDocument>

