<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0305</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-05-17</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001396838</issuerCik>
        <issuerName>Dolan Co.</issuerName>
        <issuerTradingSymbol>NYSE: DM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001205409</rptOwnerCik>
            <rptOwnerName>CHRISTIANSON TONY</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THE DOLAN COMPANY</rptOwnerStreet1>
            <rptOwnerStreet2>222 S. NINTH STREET, SUITE 2300</rptOwnerStreet2>
            <rptOwnerCity>MINNEAPOLIS</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55402</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>2012-05-17</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5974</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6965</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1300</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Adam Smith Companies, LLC</value>
                    <footnoteId id="F2"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12880</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Adam Smith Growth Partners, L.P.</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>351895</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By Adam Smith Fund, L.L.C</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">These are restricted shares of common stock issued under the Issuer's 2007 Incentive Compensation Plan (as amended and restated). 25% of the shares vested on the date of the award, and the remaining 75% of the shares will vest in three equal annual installments on each of May 17, 2013, 2014, and 2015.</footnote>
        <footnote id="F2">Mr. Christianson is the chairman of Adam Smith Companies, LLC and disclaims beneficial ownership of the reported securities, except to the extent of his pecuniary interest therein.  The filing of this report is not an admission that Mr. Christianson is the beneficial owner of the reported securities for purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F3">Mr. Christianson is the chairman of Adam Smith Companies, LLC, the general partner of Adam Smith Growth Partners, L.P. Mr. Christianson disclaims beneficial ownership of the reported securities, except to the extent of his pecuniary interest therein.  The filing of this report is not an admission that Mr. Christianson is the beneficial owner of the reported securities for purposes of Section 16 or for any other purpose.</footnote>
        <footnote id="F4">Mr. Christianson is the president of Adam Smith Management, LLC, the managing member of Adam Smith Fund, LLC. Mr. Christianson disclaims beneficial ownership of the reported securities, except to the extent of his pecuniary interest therein.  The filing of this report is not an admission that Mr. Christianson is the beneficial owner of the reported securities for purposes of Section 16 or for any other purpose</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>Kelly Jacobus, as Attorney-in-Fact for Tony Christianson.</signatureName>
        <signatureDate>2012-05-21</signatureDate>
    </ownerSignature>
</ownershipDocument>
