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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2022-09-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001581760</issuerCik>
        <issuerName>Life360, Inc.</issuerName>
        <issuerTradingSymbol>360.AX</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001932498</rptOwnerCik>
            <rptOwnerName>Hulls Chris</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O LIFE360, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>539 BRYANT STREET, SUITE 402</rptOwnerStreet2>
            <rptOwnerCity>SAN FRANCISCO</rptOwnerCity>
            <rptOwnerState>CA</rptOwnerState>
            <rptOwnerZipCode>94107</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2022-09-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>4574</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>11.53</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3026855</value>
                    <footnoteId id="F2"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>29960</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Held by ICCA Labs, LLC</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">This transaction is not a sale of shares by the Reporting Person. Instead, this represents shares that have been withheld by the Issuer to satisfy its income tax and withholding and remittance obligations in connection with the vesting and net settlement of previously reported restricted stock units.</footnote>
        <footnote id="F2">Includes 1,686,552 shares of the Issuer's common stock underlying 5,059,656 Chess Depositary Interests (&quot;CDIs&quot;). The CDIs are traded on the Australian Securities Exchange (the &quot;ASX&quot;) and are held by CHESS Depositary Nominees Pty, Limited, a subsidiary of ASX Limited, the company that operates the ASX.  Also includes 90,377 restricted stock units, each of which represents a contingent right to receive one share of the Issuer's common stock upon vesting.</footnote>
        <footnote id="F3">Represents shares of the Issuer's common stock underlying 89,880 CDIs.</footnote>
        <footnote id="F4">The Reporting Person is a member of ICCA Labs, LLC, an entity that holds an aggregate of 133,408 shares of the Issuer's common stock underlying 400,224 CDIs. The number of shares reported herein by the Reporting Person represents his proportionate ownership interest in ICCA Labs, LLC.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Daniel Menudier, as Attorney-in-Fact</signatureName>
        <signatureDate>2022-09-12</signatureDate>
    </ownerSignature>
</ownershipDocument>
