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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2018-08-13</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

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

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001186884</rptOwnerCik>
            <rptOwnerName>GROSS MICHAEL S</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>
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            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-08-13</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>75630.0646</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2335614.0646</value>
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                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
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                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2018-08-13</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>75630.0646</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F5"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F5"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
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                <sharesOwnedFollowingTransaction>
                    <value>2259984</value>
                    <footnoteId id="F6"/>
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            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnotes</value>
                    <footnoteId id="F2"/>
                    <footnoteId id="F3"/>
                    <footnoteId id="F4"/>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>165894</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F7"/>
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            <transactionDate>
                <value>2018-08-13</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>M</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>75630.0646</value>
                    <footnoteId id="F7"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F7"/>
                </transactionPricePerShare>
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            </exerciseDate>
            <expirationDate>
                <footnoteId id="F1"/>
                <footnoteId id="F7"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, par value $0.01 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <footnoteId id="F7"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>40937.4056</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F7"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F8"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-08-13</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>E</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>9727.0111</value>
                    <footnoteId id="F8"/>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F8"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
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            <exerciseDate>
                <footnoteId id="F1"/>
                <footnoteId id="F8"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F8"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, par value $0.01 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <footnoteId id="F8"/>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>115113.9243</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F8"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F9"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2018-08-14</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F1"/>
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            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>85173.5709</value>
                    <footnoteId id="F9"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0.00</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F9"/>
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            <expirationDate>
                <footnoteId id="F9"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Common Stock, par value $0.01 per share</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>85173.5709</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>85173.5709</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>See Footnote</value>
                    <footnoteId id="F9"/>
                </natureOfOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Pursuant to the SEC staff no-action letters to Carlyle GMS Finance, Inc. (pub. Avail. Oct. 8, 2015) and 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 that has elected to be regulated as a business development company or to a closed-end investment company registered under the Investment Company Act of 1940, as amended, respectively, in either case 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>
        <footnote id="F2">Includes 200,471 shares of Solar Capital Ltd. (the &quot;Issuer&quot;) held by Solar Capital Partners Employee Stock Plan, LLC (the &quot;SCP Plan&quot;), 75,630.0646 of which is reported as purchased on this Form 4. These 75,630.0646 shares may be deemed to be repurchased due to cash settlement of previously granted restricted stock units (&quot;RSUs&quot;). The SCP Plan is controlled by Solar Capital Partners, LLC (&quot;Solar Capital Partners&quot;). Michael S. Gross and Bruce J. Spohler 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.</footnote>
        <footnote id="F3">(Continued from Footnote (2)) 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. Gross, Mr. Spohler and a grantor retained annuity trust setup by and for Mr. Gross (the &quot;GRAT&quot;) by virtue of their collective ownership interest therein. In addition, the total includes 20,000 shares of the Issuer held by the GRAT, which Mr. Gross may be deemed to directly beneficially own as the sole trustee of the GRAT. Furthermore, the total includes 39,500 shares of the Issuer directly held by Mr. Gross' profit sharing plan (the &quot;Profit Sharing Plan&quot;).</footnote>
        <footnote id="F4">(Continued from Footnote (3)) Mr. Gross may be deemed to directly beneficially own these shares as the sole participant in the Profit Sharing Plan. Mr. Gross 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. Gross is the beneficial owner of such securities for purposes of Section 16 or any other purpose.</footnote>
        <footnote id="F5">Messrs. Gross and Spohler, as administrators of the SCP Plan, elected to settle 75,630.0646 RSUs previously granted to employees by paying their cash value as contemplated by the RSUs, which cash settlement may be deemed to be a purchase of the shares underlying the previously granted RSUs. The shares that may be deemed to have been acquired were previously reported as beneficially owned due to Mr. Gross's partial pecuniary interest as described in footnotes 2, 3 and 4. The settlement was approved in advance in accordance with Rule 16b-3.</footnote>
        <footnote id="F6">These 2,259,984 shares of the Issuer are the same number of shares held prior to the settlement of RSUs in cash because this transaction may only be a deemed acquisition for purposes of Section 16. No new shares of the Issuer were actually acquired as a result of the settlement of the 75,630.0646 RSUs.</footnote>
        <footnote id="F7">RSUs with respect to 75,630.0646 shares held by the SCP Plan granted to certain of Solar Capital Partners's employees on March 4, 2015 and March 2, 2016 settled on August 13, 2018. RSUs may be settled in shares of the Issuer's common stock or the cash value thereof on a one-for-one basis at the election of the SCP Plan administrators, Messrs. Gross and Spohler. The administrators elected to settle the vested portion in cash. Messrs. Gross and Spohler may be deemed to beneficially own the shares held by the SCP Plan by virtue of their collective ownership interest in Solar Capital Partners.</footnote>
        <footnote id="F8">The RSUs with respect to 9,727.0111 shares held by the SCP Plan granted to certain of Solar Capital Partners's employees on March 2, 2016 and March 9, 2017 terminated without value. The RSUs could have been settled in shares of the Issuer's common stock or the cash value thereof on a one-for-one basis at the election of the SCP Plan administrators, Messrs. Gross and Spohler. Messrs. Gross and Spohler may be deemed to beneficially own the shares held by the SCP Plan by virtue of their collective ownership interest in Solar Capital Partners.</footnote>
        <footnote id="F9">Grants of new RSUs with respect to 85,173.5709 shares held by the SCP Plan to certain of Solar Capital Partners's employees pursuant to Restricted Stock Unit Agreements, dated August 14, 2018. Shares of the common stock of the Issuer underlying the RSUs are scheduled to vest in installments of 50% on March 1, 2020 and 50% on March 1, 2021. 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. Gross and Spohler.</footnote>
    </footnotes>

    <remarks>Chief Executive Officer, President, Chairman of the Board</remarks>

    <ownerSignature>
        <signatureName>/s/ Michael S. Gross</signatureName>
        <signatureDate>2018-08-14</signatureDate>
    </ownerSignature>
</ownershipDocument>
