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

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2010-12-21</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001492691</issuerCik>
        <issuerName>SWIFT TRANSPORTATION Co</issuerName>
        <issuerTradingSymbol>SWFT</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0000901736</rptOwnerCik>
            <rptOwnerName>MOYES JERRY</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>SWIFT TRANSPORTATION COMPANY</rptOwnerStreet1>
            <rptOwnerStreet2>2200 SOUTH 75TH AVENUE</rptOwnerStreet2>
            <rptOwnerCity>PHOENIX</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85043</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>1</isOther>
            <officerTitle>CEO</officerTitle>
            <otherText>Member of 10% group</otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001272829</rptOwnerCik>
            <rptOwnerName>MOYES VICKIE</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>P.O. BOX 1397</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>TOLLESON</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85353</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001092565</rptOwnerCik>
            <rptOwnerName>MOYES JERRY &amp; VICKIE FAMILY TRUST</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O SWIFT AVIATION GROUP, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>2710 E. OLD TOWER ROAD</rptOwnerStreet2>
            <rptOwnerCity>PHOENIX</rptOwnerCity>
            <rptOwnerState>AZ</rptOwnerState>
            <rptOwnerZipCode>85034</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-02-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6000000</value>
                    <footnoteId id="F1"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17978782</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Manager</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-02-08</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>6000000</value>
                    <footnoteId id="F3"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>6000000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Member</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-05-31</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2346702</value>
                    <footnoteId id="F5"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Member</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-05-31</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2346702</value>
                    <footnoteId id="F6"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>20325484</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Manager</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-10-04</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2366685</value>
                    <footnoteId id="F7"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>17958799</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F2"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Manager</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-10-04</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1955631</value>
                    <footnoteId id="F8"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>1955631</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F4"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Manager</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-10-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1955631</value>
                    <footnoteId id="F9"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>11113203</value>
                    <footnoteId id="F10"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F11"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <transactionDate>
                <value>2013-10-23</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>5</transactionFormType>
                <transactionCode>G</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>2366685</value>
                    <footnoteId id="F12"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>0</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>2366685</value>
                    <footnoteId id="F13"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F14"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Manager and Member</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>3069599</value>
                    <footnoteId id="F15"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F16"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Member</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8323388</value>
                    <footnoteId id="F17"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>I</value>
                    <footnoteId id="F16"/>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>Member</value>
                </natureOfOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class A Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>100</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>72215</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
        <nonDerivativeHolding>
            <securityTitle>
                <value>Class B Common Stock</value>
            </securityTitle>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>8519200</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F18"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeHolding>
    </nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Forward Sale Contract (obligation to sell)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F19"/>
                <footnoteId id="F20"/>
                <footnoteId id="F21"/>
                <footnoteId id="F22"/>
                <footnoteId id="F23"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-12-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F19"/>
                <footnoteId id="F20"/>
                <footnoteId id="F21"/>
                <footnoteId id="F22"/>
                <footnoteId id="F23"/>
                <footnoteId id="F24"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F19"/>
                    <footnoteId id="F20"/>
                    <footnoteId id="F21"/>
                    <footnoteId id="F22"/>
                    <footnoteId id="F23"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2013-12-31</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-12-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>72215</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F24"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Forward Sale Contract (obligation to sell)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F19"/>
                <footnoteId id="F20"/>
                <footnoteId id="F21"/>
                <footnoteId id="F22"/>
                <footnoteId id="F23"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-12-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F19"/>
                <footnoteId id="F20"/>
                <footnoteId id="F21"/>
                <footnoteId id="F22"/>
                <footnoteId id="F23"/>
                <footnoteId id="F25"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F19"/>
                    <footnoteId id="F20"/>
                    <footnoteId id="F21"/>
                    <footnoteId id="F22"/>
                    <footnoteId id="F23"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2013-12-31</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-12-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>8519200</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F25"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Forward Sale Contract (obligation to sell)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F19"/>
                <footnoteId id="F20"/>
                <footnoteId id="F21"/>
                <footnoteId id="F22"/>
                <footnoteId id="F23"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2010-12-21</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F19"/>
                <footnoteId id="F20"/>
                <footnoteId id="F21"/>
                <footnoteId id="F22"/>
                <footnoteId id="F23"/>
                <footnoteId id="F26"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F19"/>
                    <footnoteId id="F20"/>
                    <footnoteId id="F21"/>
                    <footnoteId id="F22"/>
                    <footnoteId id="F23"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2013-12-31</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-12-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>9994112</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F26"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Forward Sale Contract (obligation to sell)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F27"/>
                <footnoteId id="F28"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2011-01-20</value>
            </transactionDate>
            <deemedExecutionDate></deemedExecutionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>J</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F27"/>
                <footnoteId id="F28"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>1</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F27"/>
                    <footnoteId id="F28"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <value>2013-12-31</value>
            </exerciseDate>
            <expirationDate>
                <value>2013-12-31</value>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Class A Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>1119091</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                    <footnoteId id="F26"/>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">The reported securities were transferred from M Capital Group Investors, LLC to Cactus Holding Company, LLC.</footnote>
        <footnote id="F2">Shares are owned directly by M Capital Group Investors, LLC, and indirectly by the Jerry and Vickie Moyes Family Trust, as the sole manager of M Capital Group Investors, LLC.  The reporting persons disclaim any beneficial ownership of these securities except to the extent of their pecuniary interest therein, and the inclusion of those shares in this report shall not be deemed an admission of beneficial ownership of these shares for Section 16 purposes.</footnote>
        <footnote id="F3">The reported securites were transferred to Cactus Holding Company, LLC from M Capital Group Investors, LLC.</footnote>
        <footnote id="F4">Shares are held by Cactus Holding Company, LLC an entity controlled by the Jerry and Vickie Moyes Family Trust, of which Mr. and Mrs. Moyes serve as co-trustees.</footnote>
        <footnote id="F5">The reported securities were transferred from Cactus Holding Company, LLC to M Capital Group Investors, LLC.  The number of securities held following this transaction reflects the transfer of 3,653,298 shares from Cactus Holding Company, LLC to the Jerry and Vickie Moyes Family Trust on March 14, 2013.</footnote>
        <footnote id="F6">The reported securities were transferred to M Capital Group Investors, LLC from Cactus Holding Company, LLC.</footnote>
        <footnote id="F7">The reported securities were transferred from M Capital Group Investors, LLC to the Michael J. Moyes Trust, the Lyndee Moyes Nester Trust, the Todd Moyes Trust, the Hollie Moyes Trust, the Chris Moyes Trust, the Marti Lyn Moyes Trust, and Cactus Holding Company, LLC.</footnote>
        <footnote id="F8">The reported securities were transferred to Cactus Holding Company, LLC from M Capital Group Investors, LLC.</footnote>
        <footnote id="F9">The reported securities were transferred from the Jerry and Vickie Moyes Family Trust to M Capital Group Investors II, LLC.</footnote>
        <footnote id="F10">Reflects the transfer of 1,955,631 shares from Cactus Holding Company, LLC to the Jerry and Vickie Moyes Family Trust on October 16, 2013.  Such transfer constitutes a mere change in form of indirect beneficial ownership, and is therefore not separately reported.</footnote>
        <footnote id="F11">Shares are owned by the Jerry and Vickie Moyes Family Trust, of which Mr. and Mrs. Moyes share voting and investment control.</footnote>
        <footnote id="F12">The reported securities were transferred to M Capital Group Investors II, LLC from the Jerry and Vickie Moyes Family Trust, the Michael J. Moyes Trust, the Lyndee Moyes Nester Trust, the Todd Moyes Trust, the Hollie Moyes Trust, the Chris Moyes Trust, and the Marti Lyn Moyes Trust.</footnote>
        <footnote id="F13">Includes 411,054 shares that were transferred by the Michael J. Moyes Trust, the Lyndee Moyes Nester Trust, the Todd Moyes Trust, the Hollie Moyes Trust, the Chris Moyes Trust, and the Marti Lyn Moyes Trust, along with 1,955,631 shares transferred by the Jerry and Vickie Moyes Family Trust, to M Capital Group Investors II, LLC on October 23, 2013.</footnote>
        <footnote id="F14">Shares are owned directly by M Capital Group Investors II, LLC, and indirectly by the Jerry and Vickie Moyes Family Trust, as the sole manager of M Capital Group Investors II, LLC.  Jerry Moyes, Jerry and Vickie Moyes, jointly, and the Jerry and Vickie Moyes Family Trust are also certain of the members of M Capital Group Investors II, LLC.  The reporting persons disclaim any beneficial ownership of these securities except to the extent of their pecuniary interest therein, and the inclusion of those shares in this report shall not be deemed an admission of beneficial ownership of these shares for Section 16 purposes.</footnote>
        <footnote id="F15">Includes 280,000 shares that were previously held by the Jerry and Vickie Moyes Family Trust which were transferred to Cactus Holding Company II, LLC on April 19, 2013.  Such transfer constitutes a mere change in form of indirect beneficial ownership, and is therefore not seperately reported.</footnote>
        <footnote id="F16">Shares are  held by Cactus Holding Company II, LLC, an entity controlled by the Jerry and Vickie Moyes Family Trust, of which Mr. and Mrs. Moyes serve as co-trustees.</footnote>
        <footnote id="F17">Includes 3,653,298 shares that were previously held by the Jerry and Vickie Moyes Family Trust which were transferred to Cactus Holding Company II, LLC on April 8, 2013.  Such shares were previously transferred from Cactus Holding Company, LLC to the Jerry and Vickie Moyes Family Trust on March 14, 2013.</footnote>
        <footnote id="F18">Shares are owned by Jerry Moyes and  Vickie Moyes, over which Mr. and Mrs. Moyes share voting and investment control.</footnote>
        <footnote id="F19">On December 21, 2010, in connection with an offering of $0.66 Trust Issued Mandatory Common Exchange Securities (the &quot;Securities&quot;) issued by the 2010 Swift Mandatory Common Exchange Security Trust (the &quot;Trust&quot;) to qualified institutional investors, Jerry Moyes, in his individual capacity, Jerry and Vickie Moyes jointly, and the Jerry and Vickie Moyes Family Trust (the &quot;JVMF Trust&quot; and, collectively with Jerry Moyes and Jerry and Vickie Moyes jointly, &quot;Sellers&quot;) entered into forward purchase contracts (each a &quot;Contract&quot; and collectively, the &quot;Contracts&quot;) with the Trust, which together with the trustees thereof acting in their capacity as such, are referred to herein as &quot;Purchaser.&quot; Purchaser is unrelated to Sellers.</footnote>
        <footnote id="F20">Mr. Moyes, Mr. and Mrs. Moyes jointly, and the JVMF Trust are obligated under the Contracts to deliver to Purchaser for the holders of the Securities on December 31, 2013 (the &quot;Exchange Date&quot;) up to 72,215, 8,519,200, and 11,113,203 (including 1,119,091 shares pursuant to the  exercise of the Option described in footnotes 27 and 28) shares, respectively, of Class A Common Stock, par value $0.01 per share, of Swift Transportation Company (&quot;Common Stock&quot;), with the exact number of shares to be delivered determined in accordance with the &quot;Exchange Rate&quot; set forth in the Contracts.</footnote>
        <footnote id="F21">To secure their obligations under the Contracts, Mr. Moyes, Mr. and Mrs. Moyes jointly, and the JVMF trust committed 72,215, 8,519,200, and 11,113,203 (including 1,119,091 shares pursuant to the exercise of the Option described in footnotes 27 and 28), shares respectively, of Class B Common Stock, par value $0.01 per share, of Swift Transportation Company (&quot;Contract Stock&quot;) during the term of the Contracts, although the Sellers retain beneficial ownership of the Contract Stock during such term.</footnote>
        <footnote id="F22">The number of shares of Common Stock that must be delivered on the Exchange Date is determined in accordance with the &quot;Exchange Rate&quot; set forth in the Contracts. The Exchange Rate is determined based on the &quot;Average Market Price&quot;. The &quot;Average Market Price&quot; is the average &quot;Closing Price&quot; (as defined in the Contracts) per share of Common Stock for the 20 &quot;Trading Days&quot; (as defined in the Contracts) immediately prior to but not including the third Trading Day prior to the Exchange Date. The Sellers may elect to settle the Contracts, in whole or in part, by delivering cash in lieu of Common Stock to Purchaser in an amount equal to the value (as determined at the Average Market Price) of the Common Stock Sellers would otherwise be required to deliver.</footnote>
        <footnote id="F23">If the Average Market Price is less than $11.00, the Sellers are obligated to deliver to the Trust all 19,704,618 shares of Common Stock underlying the Contracts. If the Average Market Price is less than $13.48 but equal to or greater than $11.00, Sellers are obligated to deliver to the Trust a number of shares of Common Stock having a value (as determined at the Average Market Price) equal to $216,750,798. If the Average Market Price is equal to or greater than $13.48, Sellers are obligated to deliver to the Trust 16,084,879 shares of Common Stock. As consideration for entering into the Contracts, the Sellers received an aggregate amount of $170,548,699.29(including $9,723,955.21 received by the JVMF Trust pursuant to the exercise of the Option described in footnotes 27 and 28).</footnote>
        <footnote id="F24">This transaction represents the Contract entered into by Jerry Moyes in his individual capacity.</footnote>
        <footnote id="F25">This transaction represents the Contract entered into by Jerry Moyes and Vickie Moyes, jointly.  The shares subject to this Contract are held by Mr. and Mrs. Moyes, jointly, and Mr. and Mrs. Moyes share voting and investment control over such shares.</footnote>
        <footnote id="F26">This transaction represents the Contract entered into by the JVMF Trust.  The shares subject to this Contract are owned by the JVMF Trust, of which Mr. and Mrs. Moyes are co-trustees and share voting and investment control.</footnote>
        <footnote id="F27">Under the JVMF Trust's Contract, the JVMF Trust was obligated to sell, and the Trust was obligated to buy, up to an additional 3,409,091 shares of Common Stock if and to the extent that the initial purchasers of the Securities exercised an overallotment option (the &quot;Option&quot;) to purchase additional Securities from the Trust.  On January 14, 2011, the initial purchasers of the Securities exercised the Option with respect to 1,119,091 additional Securities.</footnote>
        <footnote id="F28">Pursuant to this exercise, the JVMF Trust became irrevocably obligated to commit, and did commit, 1,119,091 shares of Contract Stock under its Contract on January 20, 2011, for which the JVMF Trust received $9,723,955.21.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Jerry Moyes, by Earl Scudder, attorney-in-fact, pursuant to a POA filed herewith</signatureName>
        <signatureDate>2013-10-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Vickie Moyes, by Earl Scudder, attorney-in-fact, pursuant to a POA filed herewith</signatureName>
        <signatureDate>2013-10-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Vickie Moyes, Co-Trustee of the Jerry and Vickie Moyes Family Trust, by Earl Scudder, attorney-in-fact, pursuant to a POA filed herewith</signatureName>
        <signatureDate>2013-10-31</signatureDate>
    </ownerSignature>

    <ownerSignature>
        <signatureName>/s/ Jerry Moyes, Co-Trustee of the Jerry and Vickie Moyes Family Trust, by Earl Scudder, attorney-in-fact, pursuant to a POA filed herewith</signatureName>
        <signatureDate>2013-10-31</signatureDate>
    </ownerSignature>
</ownershipDocument>
