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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2017-11-08</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001437578</issuerCik>
        <issuerName>BRIGHT HORIZONS FAMILY SOLUTIONS INC.</issuerName>
        <issuerTradingSymbol>BFAM</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001040508</rptOwnerCik>
            <rptOwnerName>BAIN CAPITAL INVESTORS LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 CLARENDON STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001379521</rptOwnerCik>
            <rptOwnerName>BCIP Trust Associates III-B</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 CLARENDON STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001430079</rptOwnerCik>
            <rptOwnerName>BCIP Associates-G</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 CLARENDON STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001691138</rptOwnerCik>
            <rptOwnerName>BC BRIGHTNESS SPV GP, LLC</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 CLARENDON STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001691137</rptOwnerCik>
            <rptOwnerName>BC Brightness SPV, LP</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>200 CLARENDON STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>BOSTON,</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02116</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2017-11-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
                <footnoteId id="F2"/>
                <footnoteId id="F3"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>416426</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7986532</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                    <footnoteId id="F5"/>
                    <footnoteId id="F6"/>
                    <footnoteId id="F7"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <footnotes>
        <footnote id="F1">Bain Capital Investors, LLC (&quot;BCI&quot;) is the sole member of BC Brightness SPV GP, LLC (&quot;BC SPV GP&quot;), which is the sole general partner of BC Brightness SPV, LP (&quot;BC SPV&quot;). As a result, BC SPV GP may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by BC SPV. BC SPV GP disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein. On November 8, 2017, BC SPV distributed 413,738 shares of Common Stock to one or more members or partners in connection with certain charitable gifts made on November 8, 2017. Following such distribution, BC SPV held 7,892,279 shares of Common Stock.</footnote>
        <footnote id="F2">On November 8, 2017, BCIP Associates III, LLC (&quot;BCIP III&quot;), whose manager is BCIP Associates III (&quot;BCIPA III&quot;), whose managing partner is Boylston Coinvestors, LLC (&quot;Boylston&quot;), distributed 2,605 shares of Common Stock to one or more of its members or partners in connection with certain charitable gifts made on November 8, 2017. Following such distribution, BCIP III held 55,627 shares of Common Stock. BCIPA III may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by BCIP III. BCIPA III disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.</footnote>
        <footnote id="F3">On November 8, 2017, BCIP Associates III-B, LLC (&quot;BCIP III-B&quot;), whose manager is BCIP Associates III-B (&quot;BCIPA III-B&quot;), whose managing partner is Boylston, distributed 83 shares of Common Stock to one or more of its members or partners in connection with certain charitable gifts made on November 8, 2017.  Following such distribution, BCIP III-B held 10,489 shares of Common Stock. BCIPA III-B may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by BCIP III-B. BCIPA III-B disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.</footnote>
        <footnote id="F4">As of November 8, 2017, BCIP T Associates III, LLC (&quot;BCIPT III&quot;), whose manager is BCIP Trust Associates III (&quot;BCIPTA III&quot;), whose managing partner is Boylston, held 25,285 shares of Common Stock. BCIPTA III may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by BCIPT III. BCIPTA III disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.</footnote>
        <footnote id="F5">As of November 8, 2017, BCIP T Associates III-B, LLC (&quot;BCIPT III-B&quot;), whose manager is BCIP Trust Associates III-B (&quot;BCIPTA III-B&quot;), whose managing partner is Boylston, held 1,751 shares of Common Stock. BCIPTA III-B may be deemed to share voting and dispositive power with respect to the shares of Common Stock held by BCIPT III-B. BCIPTA III-B disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.</footnote>
        <footnote id="F6">As of November 8, 2017, BCIP Associates-G (&quot;BCIP G&quot; and together with BC SPV, BCIP III, BCIP III-B, BCIPT III and BCIPT III-B, the &quot;Bain Capital Entities&quot;), whose managing partner is Boylston, held 1,101 shares of Common Stock.</footnote>
        <footnote id="F7">The governance, investment strategy and decision-making process with respect to the investments held by the Bain Capital Entities is directed by the Global Private Equity Board of BCI. As a result, BCI may be deemed to share voting and dispositive power with respect to all of the shares of Common Stock held by the Bain Capital Entities. BCI disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein.</footnote>
    </footnotes>

    <remarks>Form 2 of 2</remarks>

    <ownerSignature>
        <signatureName>Bain Capital Investors, LLC, By: /s/ Joshua Bekenstein, Name: Joshua Bekenstein, Title: Managing Director</signatureName>
        <signatureDate>2017-11-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BCIP Trust Associates III-B, By: Boylston Coinvestors, LLC, as Managing Partner, By: /s/ Joshua Bekenstein, Name: Joshua Bekenstein, Title: Authorized Signatory</signatureName>
        <signatureDate>2017-11-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BCIP Associates-G, By: Boylston Coinvestors, LLC, as Managing Partner, By: /s/ Joshua Bekenstein, Name: Joshua Bekenstein, Title: Authorized Signatory</signatureName>
        <signatureDate>2017-11-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BC Brightness SPV GP, LLC, By: Bain Capital Investors, LLC, it's Sole Member, By: /s/ Joshua Bekenstein, Name: Joshua Bekenstein, Title: Managing Director</signatureName>
        <signatureDate>2017-11-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BC BRIGHTNESS SPV, LP, By: BC Brightness SPV GP, LLC, its General Partner, By:  Bain Capital Investors, LLC, its Sole Member, By: /s/ Joshua Bekenstein, Name: Joshua Bekenstein, Title: Managing Director</signatureName>
        <signatureDate>2017-11-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
