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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2015-05-11</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001602367</issuerCik>
        <issuerName>Adeptus Health Inc.</issuerName>
        <issuerTradingSymbol>ADPT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001352791</rptOwnerCik>
            <rptOwnerName>Rosenberg Daniel</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O STERLING PARTNERS, 401 NORTH</rptOwnerStreet1>
            <rptOwnerStreet2>MICHIGAN AVENUE, SUITE 3300</rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60611</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001611341</rptOwnerCik>
            <rptOwnerName>Hosler Daniel J.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O STERLING PARTNERS, 401 NORTH</rptOwnerStreet1>
            <rptOwnerStreet2>MICHIGAN AVENUE, SUITE 3300</rptOwnerStreet2>
            <rptOwnerCity>CHICAGO</rptOwnerCity>
            <rptOwnerState>IL</rptOwnerState>
            <rptOwnerZipCode>60611</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2015-05-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>S</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>842704</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>60.08</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3317817</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F7"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3410</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Units of Adeptus Health LLC</value>
                <footnoteId id="F4"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2015-05-11</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F5"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>1132475</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>60.08</value>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1132475</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4458674</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnotes</value>
                    <footnoteId id="F6"/>
                    <footnoteId id="F7"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">This amount represents the $63.75 public offering price per share of Class A Common Stock of Adeptus Health, Inc. (the &quot;Issuer&quot;), less the underwriting discount of $3.665624 per share.</footnote>
        <footnote id="F2">Shares of Class A Common Stock of the Issuer are held by SCP III AIV THREE-FCER Conduit, L.P.</footnote>
        <footnote id="F3">Represents restricted shares of Class A Common Stock of the Issuer granted to Daniel W. Rosenberg and Daniel J. Hosler as members of the board of directors of the Issuer. Messrs. Rosenberg and Hosler are employees of Sterling Fund Management, LLC and hold such restricted shares of Class A Common Stock for and on behalf of Sterling Fund Management, LLC, which acts as an advisor to SCP III AIV THREE-FCER, L.P. and SCP III AIV THREE-FCER Conduit, L.P. (the &quot;Sterling Funds&quot;). A portion of the proceeds of any disposition of these securities will be applied against management fees attributable to limited partners of the Sterling Funds which are payable to the advisor. Sterling Fund Management, LLC is wholly-owned by Sterling Fund Management Holdings, L.P., whose general partner, Sterling Fund Management Holdings GP, LLC is managed by Messrs. Steven M. Taslitz, Merrick M. Elfman, Douglas L. Becker, Eric D. Becker and R. Christopher Hoehn-Saric.</footnote>
        <footnote id="F4">Units of Adeptus Health LLC represent limited liability company units of Adeptus Health LLC and an equal number of shares of Class B Common Stock of the Issuer, which together are exchangeable on a one-for-one basis for shares of Class A Common Stock of the Issuer pursuant to the Amended and Restated Limited Liability Company Agreement of Adeptus Health LLC.</footnote>
        <footnote id="F5">Represents a purchase of limited liability company units of Adeptus Health LLC by the Issuer from SCP III AIV THREE-FCER, L.P. at $63.75 per share, the public offering price per share of Class A Common Stock, less an amount equal to the underwriting discount of $3.665624 per share. In connection with the purchase, an equivalent number of shares of Class B Common Stock of the Issuer were cancelled.</footnote>
        <footnote id="F6">Units of Adeptus Health LLC are held by SCP III AIV THREE-FCER, L.P.</footnote>
        <footnote id="F7">Sterling Capital Partners III, LLC is the general partner of SC Partners III, L.P., the general partner of each of the Sterling Funds. Messrs. Steven M. Taslitz, Merrick M. Elfman, Douglas L. Becker, Eric D. Becker and R. Christopher Hoehn-Saric are the managers of Sterling Capital Partners III, LLC. Messrs. Rosenberg and Hosler also have an indirect interest in the securities of the Issuer held by the Sterling Funds.</footnote>
    </footnotes>

    <remarks>Each of the Reporting Persons disclaims beneficial ownership of the securities reported herein, except to the extent of such Reporting Person's pecuniary interest therein, if any. The filing of this statement shall not be deemed to be an admission that, for purposes of Section 16 of the Securities Exchange Act of 1934 or otherwise, the Reporting Persons are the beneficial owners of any securities reported herein. Because no more than 10 reporting persons can file any one Form 4 through the Securities and Exchange Commission's EDGAR system, SCP III AIV THREE-FCER, L.P., SCP III AIV THREE-FCER Conduit, L.P., SC Partners III, L.P., Sterling Capital Partners III, LLC, and Messrs. Taslitz, Elfman, D. Becker, E. Becker and Hoehn-Saric have made a separate Form 4 filing.</remarks>

    <ownerSignature>
        <signatureName>/s/ M. Avi Epstein, attorney-in-fact for Daniel W. Rosenberg</signatureName>
        <signatureDate>2015-05-13</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ M. Avi Epstein, attorney-in-fact for Daniel J. Hosler</signatureName>
        <signatureDate>2015-05-13</signatureDate>
    </ownerSignature>
</ownershipDocument>
