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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2012-09-14</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000023666</issuerCik>
        <issuerName>Hillshire Brands Co</issuerName>
        <issuerTradingSymbol>HSH</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001552992</rptOwnerCik>
            <rptOwnerName>Hayes Thomas P</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O THE HILLSHIRE BRANDS COMPANY</rptOwnerStreet1>
            <rptOwnerStreet2>3500 LACEY ROAD</rptOwnerStreet2>
            <rptOwnerCity>DOWNERS GROVE</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60515</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>EVP, Chief Supply Chain Off</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>common stock</value>
            </securityTitle>
            <transactionDate>
                <value>2012-09-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>3494</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>27124</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Represents restricted stock units (RSUs) granted upon conversion of performance stock units (PSUs).  In anticipation of the spin-off of its international coffee and tea business that was completed on June 28, 2012, in fiscal 2012 the company granted PSUs under its FY12-14 long-term equity incentive program with a value equal to one-third of the annual grant amount.  These PSUs were converted into RSUs to the extent the company achieved a one-year operating income target for fiscal 2012.  The RSUs will settle and be converted into shares of common stock, on a one-for-one basis, on August 31, 2014, subject to the reporting person's continued employment through that date.</footnote>
        <footnote id="F2">Includes 3,494 RSUs that will be converted into shares of common stock, on a one-for-one basis, upon vesting.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Helen N. Kaminski, for Thomas P. Hayes pursuant to power of attorney previously filed.</signatureName>
        <signatureDate>2012-09-18</signatureDate>
    </ownerSignature>
</ownershipDocument>
