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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2016-11-28</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>2016-11-28</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1731904</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>71.11</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>12511406</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;). BCI is also the sole general partner of Bain Capital Partners X, L.P. (&quot;BCP X&quot;), which is the sole general partner of Bain Capital Fund X, L.P. (&quot;Fund X&quot;). Fund X is a limited partner of BC SPV. As a result, BC SPV GP may be deemed to share voting and dispositive power with respect to shares of Common Stock held by BC SPV. In addition, BCP X may be deemed to share voting and dispositive power with respect to shares of Common Stock held by Fund X. Each of BC SPV GP and BCP X disclaims beneficial ownership of such securities except to the extent of its pecuniary interest therein. On November 28, 2016, Fund X sold 1,710,547 shares of Common Stock.  Fund X's remaining 12,366,883 shares of Common Stock have been transferred to BC SPV in a transaction that is exempt from Section 16 pursuant to Rule 16a-13.</footnote>
        <footnote id="F2">On November 28, 2016, 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;), sold 12,144 shares of Common Stock. Following such sale, BCIP III held 86,815 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 28, 2016, 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, sold 2,516 shares of Common Stock Following such sale, BCIP III-B held 15,761 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">On November 28, 2016, 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, sold 6,018 shares of Common Stock. Following such sale, BCIPT III held 37,696 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">On November 28, 2016, 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, sold 417 shares of Common Stock. Following such sale, BCIPT III-B held 2,610 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">On November 28, 2016, BCIP Associates-G (&quot;BCIP G&quot; and together with Fund X, BC SPV, BCIP III, BCIP III-B, BCIPT III and BCIPT III-B, the &quot;Bain Capital Entities&quot;), whose managing partner is Boylston, sold 262 shares of Common Stock. Following such sale, BCIP G held 1,641 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>BCIP Trust Associates III-B, By: Boylston Coinvestors, LLC, as Managing Partner, By: /s/ David Humphrey, Name: David Humphrey, Title: Authorized Signatory</signatureName>
        <signatureDate>2016-11-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BCIP Associates-G, By: Boylston Coinvestors, LLC, as Managing Partner, By: /s/ David Humphrey, Name: David Humphrey, Title: Authorized Signatory</signatureName>
        <signatureDate>2016-11-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>BC Brightness SPV GP, LLC, By: Bain Capital Investors, LLC, its Managing Member, By: /s/ David Humphrey, Name: David Humphrey, Title: Managing Director</signatureName>
        <signatureDate>2016-11-30</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/ David Humphrey, Name: David Humphrey, Title: Managing Director</signatureName>
        <signatureDate>2016-11-30</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>Bain Capital Investors, LLC, By: By: /s/ David Humphrey, Name: David Humphrey, Title: Authorized Signatory</signatureName>
        <signatureDate>2016-11-30</signatureDate>
    </ownerSignature>
</ownershipDocument>
