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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2021-10-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001596946</issuerCik>
        <issuerName>Quotient Ltd</issuerName>
        <issuerTradingSymbol>QTNT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001475995</rptOwnerCik>
            <rptOwnerName>Mendez Manuel O.</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O QUOTIENT LIMITED, B1, BUSINESS PARK</rptOwnerStreet1>
            <rptOwnerStreet2>TERRE BONNE, ROUTE DE CRASSIER 13</rptOwnerStreet2>
            <rptOwnerCity>EYSINS</rptOwnerCity>
            <rptOwnerState>V8</rptOwnerState>
            <rptOwnerZipCode>1262</rptOwnerZipCode>
            <rptOwnerStateDescription>SWITZERLAND</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Chief Executive Officer</officerTitle>
        </reportingOwnerRelationship>
    </reportingOwner>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Restricted Stock Units</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-10-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>181159</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>3.68</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F2"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F2"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Ordinary Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>181159</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>887681</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Ordinary Share Option
(Right to Buy)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <value>3.68</value>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2021-10-15</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionTimeliness>
                <value></value>
            </transactionTimeliness>
            <transactionAmounts>
                <transactionShares>
                    <value>138227</value>
                </transactionShares>
                <transactionPricePerShare>
                    <value>2.41</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <value>2031-04-01</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Ordinary Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>138227</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>718788</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Restricted Stock Units convert into ordinary shares on a one-for-one basis.</footnote>
        <footnote id="F2">The reporting person and Quotient Ltd. mutually agreed to cancel 181,159 Restricted Stock Units (RSUs) and 138,227 options and in lieu thereof to pay to the reporting person $1,000,000 in cash, net of social security and tax cost deductions, to support the reporting person's relocation to Switzerland where Quotient Ltd.'s principal executive offices are located. Of the remaining RSUs,163,043 will vest in three equal annual installments beginning April 1, 2022, and the balance will vest over three years with 50% vesting on April 1, 2022 and the balance vesting proportionately over the remaining two years.</footnote>
        <footnote id="F3">The reporting person and Quotient Ltd. mutually agreed to cancel 181,159 RSUs and 138,227 options and in lieu thereof to pay to the reporting person $1,000,000 in cash, net of social security and tax cost deductions, to support the reporting person's relocation to Switzerland where Quotient Ltd.'s principal executive offices are located. The remaining options will vest in three equal annual installments beginning on April 1, 2022.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Manuel O. Mendez, by Rebecca Cho his attorney in fact</signatureName>
        <signatureDate>2021-10-19</signatureDate>
    </ownerSignature>
</ownershipDocument>
