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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2014-02-26</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001100962</issuerCik>
        <issuerName>ENDO HEALTH SOLUTIONS INC.</issuerName>
        <issuerTradingSymbol>ENDP</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001554635</rptOwnerCik>
            <rptOwnerName>Farhat Camille</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O AMERICAN MEDICAL SYSTEMS</rptOwnerStreet1>
            <rptOwnerStreet2>10700 BREN ROAD WEST</rptOwnerStreet2>
            <rptOwnerCity>MINNETONKA</rptOwnerCity>
            <rptOwnerState>MN</rptOwnerState>
            <rptOwnerZipCode>55343</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>President, AMS, Inc.</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>2010 Stock Incentive Plan Performance Shares</value>
                <footnoteId id="F1"/>
            </securityTitle>
            <transactionDate>
                <value>2014-02-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>10832</value>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>18128</value>
                    <footnoteId id="F4"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>2010 Stock Incentive Plan Restricted Share Units (RSU)</value>
                <footnoteId id="F5"/>
            </securityTitle>
            <transactionDate>
                <value>2014-02-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>5416</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>21394</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock, par value, $.01 per share</value>
            </securityTitle>
            <transactionDate>
                <value>2014-02-27</value>
                <footnoteId id="F6"/>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>239</value>
                    <footnoteId id="F7"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>79.82</value>
                    <footnoteId id="F8"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>4031</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>2010 Stock Incentive Plan Stock Options (NQ)</value>
                <footnoteId id="F9"/>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>79.33</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2014-02-26</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>20182</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                    <footnoteId id="F3"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F10"/>
            </exerciseDate>
            <expirationDate>
                <value>2024-02-26</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>20182</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>91359</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The performance shares vest upon the Company achieving certain shareholder return targets over a cumulative 3-year period.</footnote>
        <footnote id="F2">Represents target quantity of shares issuable. The exact number of shares issuable will be determined on achievement of certain shareholder return targets over a cumulative 3-year period, as determined by the Board of Directors of Endo Health Solutions Inc. The executive can earn between 0% and 300% of the target shares.</footnote>
        <footnote id="F3">These securities were granted to Mr. Farhat in consideration of his services as the President of American Medical Systems, a subsidiary of Endo Health Solutions Inc.</footnote>
        <footnote id="F4">Represents the cumulative target quantity of shares issuable with respect to all 2010 Stock Incentive Plan performance shares outstanding. The cumulative total is the combination of the target payouts for the current grant and all past grants made under the 2010 Stock Incentive Plan and still outstanding, which are subject to a range of payouts depending on the achievement of certain performance metrics as described herein for the current grants and as previously disclosed for all other performance share grants.</footnote>
        <footnote id="F5">Upon each vesting date, each vested restricted stock unit automatically converts into one (1) share of Endo Health Solutions Inc. common stock. These restricted stock units (RSUs) are generally exercisable 25% per year on each of February 26, 2015, February 26, 2016, February 26, 2017 and February 26, 2018. Upon vesting, we consider the underlying RSUs</footnote>
        <footnote id="F6">Twenty-five percent (25%) of Mr. Farhat's February 27, 2013 grant of restricted stock units (RSUs) vested on February 27, 2014. Upon vesting, certain shares are delivered by the issuer to satisfy tax obligations on shares acquired.</footnote>
        <footnote id="F7">These shares represent stock withheld by the issuer to satisfy tax obligations on shares acquired upon vesting of restricted stock units.</footnote>
        <footnote id="F8">$79.82 represents the vesting price, which is the average of the high and low share price on February 27, 2014</footnote>
        <footnote id="F9">Representing the right to buy shares of common stock, par value $0.01 per share, of Endo Health Solutions Inc.</footnote>
        <footnote id="F10">These stock options are generally exercisable 25% per year on each of February 26, 2015, February 26, 2016, February 26, 2017, and February 26, 2018.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Caroline B. Manogue, by power of attorney</signatureName>
        <signatureDate>2014-02-28</signatureDate>
    </ownerSignature>
</ownershipDocument>
