<SEC-DOCUMENT>0000314808-16-000377.txt : 20160608
<SEC-HEADER>0000314808-16-000377.hdr.sgml : 20160608
<ACCEPTANCE-DATETIME>20160608171458
ACCESSION NUMBER:		0000314808-16-000377
CONFORMED SUBMISSION TYPE:	4/A
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20160601
FILED AS OF DATE:		20160608
DATE AS OF CHANGE:		20160608

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Ensco plc
		CENTRAL INDEX KEY:			0000314808
		STANDARD INDUSTRIAL CLASSIFICATION:	DRILLING OIL & GAS WELLS [1381]
		IRS NUMBER:				980635229
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		6 CHESTERFIELD GARDENS
		CITY:			LONDON
		STATE:			X0
		ZIP:			W1J5BQ
		BUSINESS PHONE:		4402076594660

	MAIL ADDRESS:	
		STREET 1:		6 CHESTERFIELD GARDENS
		CITY:			LONDON
		STATE:			X0
		ZIP:			W1J5BQ

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Ensco International plc
		DATE OF NAME CHANGE:	20091223

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ENSCO INTERNATIONAL INC
		DATE OF NAME CHANGE:	19950526

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	ENERGY SERVICE COMPANY INC
		DATE OF NAME CHANGE:	19920703

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			ROWSEY PAUL E III
		CENTRAL INDEX KEY:			0001184169

	FILING VALUES:
		FORM TYPE:		4/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-08097
		FILM NUMBER:		161704225

	MAIL ADDRESS:	
		STREET 1:		CRESCENT REAL ESTATE EQUAITIES LTD
		STREET 2:		777 MAIN STREET
		CITY:			FORT WORTH
		STATE:			TX
		ZIP:			76102
</SEC-HEADER>
<DOCUMENT>
<TYPE>4/A
<SEQUENCE>1
<FILENAME>wf-form4a_146542048619664.xml
<DESCRIPTION>FORM 4/A
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4/A</documentType>

    <periodOfReport>2016-06-01</periodOfReport>

    <dateOfOriginalSubmission>2016-06-03</dateOfOriginalSubmission>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0000314808</issuerCik>
        <issuerName>Ensco plc</issuerName>
        <issuerTradingSymbol>ESV</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001184169</rptOwnerCik>
            <rptOwnerName>ROWSEY PAUL E III</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>6 CHESTERFIELD GARDENS</rptOwnerStreet1>
            <rptOwnerStreet2>3RD FLOOR</rptOwnerStreet2>
            <rptOwnerCity>LONDON</rptOwnerCity>
            <rptOwnerState>X0</rptOwnerState>
            <rptOwnerZipCode>W1J 5BQ</rptOwnerZipCode>
            <rptOwnerStateDescription>UNITED KINGDOM</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>1</isDirector>
            <isOfficer>0</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle></officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable>
        <nonDerivativeTransaction>
            <securityTitle>
                <value>Class A Ordinary Shares</value>
            </securityTitle>
            <transactionDate>
                <value>2016-06-01</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>F</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>477</value>
                    <footnoteId id="F1"/>
                    <footnoteId id="F2"/>
                </transactionShares>
                <transactionPricePerShare>
                    <value>9.65</value>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>45914</value>
                    <footnoteId id="F3"/>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </nonDerivativeTransaction>
    </nonDerivativeTable>

    <derivativeTable></derivativeTable>

    <footnotes>
        <footnote id="F1">On June 3, 2016, the reporting person filed a Form 4 reporting that 1,158 Class A ordinary shares were withheld to satisfy tax withholding obligations that arose upon vesting.  Due to administrative error, this number was incorrectly reported.  The correct number of shares withheld to satisfy tax withholding obligations is 477.</footnote>
        <footnote id="F2">Upon the vesting of our restricted share units, the reporting person is required to pay the aggregate nominal value (par value), $0.10 per share, of our Class A ordinary shares actually issued, in accordance with U.K. corporate law.  In connection with the transaction reported above, the reporting person paid $415.30 to Ensco plc with respect to the shares actually issued upon vesting of the restricted share units.  The remaining 477 shares were withheld and not issued to satisfy certain tax withholding obligations.</footnote>
        <footnote id="F3">Represents the correct amount of securities beneficially owned following all of the reporting person's transactions that occurred on June 1, 2016.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Davor S. Vukadin, by Power of Attorney</signatureName>
        <signatureDate>2016-06-08</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
</SEC-DOCUMENT>
