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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2015-03-02</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001418076</issuerCik>
        <issuerName>Solar Capital Ltd.</issuerName>
        <issuerTradingSymbol>SLRC</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001240586</rptOwnerCik>
            <rptOwnerName>SPOHLER BRUCE J</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SOLAR CAPITAL LTD.</rptOwnerStreet1>
            <rptOwnerStreet2>500 PARK AVENUE</rptOwnerStreet2>
            <rptOwnerCity>NEW YORK</rptOwnerCity>
            <rptOwnerState>NY</rptOwnerState>
            <rptOwnerZipCode>10022</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>See Remarks</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2015-03-02</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>36784</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>20.24</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2115786</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2015-03-03</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>P</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>15452</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>20.28</value>
                    <footnoteId id="F1"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2131238</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F4"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2015-03-04</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F5"/>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>72135.2582</value>
                    <footnoteId id="F4"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F4"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F4"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, par value $0.01 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>72135.2582</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>72135.2582</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See footnote</value>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The price reported in Column 4 is a weighted average price.  These shares were purchased in multiple transactions.  The reported price for the share purchases made on March 2, 2015 is based on prices ranging from a low of $20.10 per share to a high of $20.60 per share.  The reported price for the share purchases made on March 3, 2015 is based on prices ranging from a low of $20.16 per share to a high of $20.39 per share.  The reporting person undertakes to provide to Solar Capital Ltd. (the &quot;Issuer&quot;), any security holder of the Issuer or the staff of the Securities and Exchange Commission, upon request, full information regarding the number of shares purchased at each separate price set forth above.</footnote>
        <footnote id="F2">Includes 131,225 shares of the Issuer held by Solar Capital Partners Employee Stock Plan, LLC (the &quot;SCP Plan&quot;), 52,236 of which is reported as purchased on this Form 4. The 52,236 shares acquired were purchased in the open market for the purpose of satisfying obligations related to its Restricted Stock Unit (&quot;RSU&quot;) grants. The SCP Plan is controlled by Solar Capital Partners, LLC (&quot;Solar Capital Partners&quot;). Mr. Spohler and Michael S. Gross may be deemed to indirectly beneficially own a portion of the shares held by the SCP Plan by virtue of their collective ownership interest in Solar Capital Partners.  (Continued in footnote 3)</footnote>
        <footnote id="F3">In addition, the total includes 1,285,013 shares of the Issuer held by Solar Capital Investors, LLC (&quot;Solar Capital I&quot;) and 715,000 shares of the Issuer held by Solar Capital Investors II, LLC (&quot;Solar Capital II&quot;), a portion of both of which may be deemed to be indirectly beneficially owned by Mr. Spohler, Mr. Gross and a grantor retained annuity trust setup by and for Mr. Gross by virtue of their collective ownership interest therein. Mr. Spohler disclaims beneficial ownership of any of the Issuer's securities directly held by the SCP Plan, Solar Capital I or Solar Capital II, except to the extent of his pecuniary interest therein, and this report shall not be deemed an admission that Mr. Spohler is the beneficial owner of such securities for purposes of Section 16 or any other purpose.</footnote>
        <footnote id="F4">Grants of RSUs with respect to 72,135.2582 shares held by the SCP Plan, which is controlled by Solar Capital Partners, to certain of its employees pursuant to Restricted Stock Unit Agreements, dated March 4, 2015.  Shares of the Issuer's common stock underlying these RSUs are scheduled to vest in installments of 50% on March 1, 2017 and 50% on March 1, 2018.  Upon settlement, the RSUs will become payable on a one-for-one basis in shares of the Issuer's common stock or the cash value thereof at the election of the SCP Plan administrators, Messrs. Spohler and Gross.</footnote>
        <footnote id="F5">Pursuant to the SEC staff no-action letter to Babson Capital Management LLC (pub. avail. Dec. 14, 2006), an employee benefit plan sponsored by an investment adviser (or an affiliated person of an investment adviser) to a closed-end investment company regulated under the Investment Company Act of 1940, as amended, that offers plan participants equity securities of such investment company is considered an &quot;employee benefit plan sponsored by the issuer&quot; for the purposes of Rule 16b-3 under the Securities Exchange Act of 1934, as amended.</footnote>
    </footnotes>

    <remarks>Chief Operating Officer and Director</remarks>

    <ownerSignature>
        <signatureName>/s/ Bruce J. Spohler</signatureName>
        <signatureDate>2015-03-04</signatureDate>
    </ownerSignature>
</ownershipDocument>
