<SEC-DOCUMENT>0001718360-19-000006.txt : 20190220
<SEC-HEADER>0001718360-19-000006.hdr.sgml : 20190220
<ACCEPTANCE-DATETIME>20190220132306
ACCESSION NUMBER:		0001718360-19-000006
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20190215
FILED AS OF DATE:		20190220
DATE AS OF CHANGE:		20190220

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Brown Heather
		CENTRAL INDEX KEY:			0001718360

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-31909
		FILM NUMBER:		19617738

	MAIL ADDRESS:	
		STREET 1:		141 FRONT STREET
		CITY:			HAMILTON
		STATE:			D0
		ZIP:			HM19

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ASPEN INSURANCE HOLDINGS LTD
		CENTRAL INDEX KEY:			0001267395
		STANDARD INDUSTRIAL CLASSIFICATION:	FIRE, MARINE & CASUALTY INSURANCE [6331]
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			D0
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		141 FRONT STREET
		CITY:			HAMILTON
		STATE:			D0
		ZIP:			HM 19
		BUSINESS PHONE:		1 441 295 8201

	MAIL ADDRESS:	
		STREET 1:		141 FRONT STREET
		CITY:			HAMILTON
		STATE:			D0
		ZIP:			HM 19
</SEC-HEADER>
<DOCUMENT>
<TYPE>4
<SEQUENCE>1
<FILENAME>wf-form4_155068697261281.xml
<DESCRIPTION>FORM 4
<TEXT>
<XML>
<?xml version="1.0"?>
<ownershipDocument>

    <schemaVersion>X0306</schemaVersion>

    <documentType>4</documentType>

    <periodOfReport>2019-02-15</periodOfReport>

    <notSubjectToSection16>0</notSubjectToSection16>

    <issuer>
        <issuerCik>0001267395</issuerCik>
        <issuerName>ASPEN INSURANCE HOLDINGS LTD</issuerName>
        <issuerTradingSymbol>AHL</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001718360</rptOwnerCik>
            <rptOwnerName>Brown Heather</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>141 FRONT STREET</rptOwnerStreet1>
            <rptOwnerStreet2></rptOwnerStreet2>
            <rptOwnerCity>HAMILTON</rptOwnerCity>
            <rptOwnerState>D0</rptOwnerState>
            <rptOwnerZipCode>HM19</rptOwnerZipCode>
            <rptOwnerStateDescription>BERMUDA</rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>0</isDirector>
            <isOfficer>1</isOfficer>
            <isTenPercentOwner>0</isTenPercentOwner>
            <isOther>0</isOther>
            <officerTitle>Group HR Director</officerTitle>
            <otherText></otherText>
        </reportingOwnerRelationship>
    </reportingOwner>

    <nonDerivativeTable></nonDerivativeTable>

    <derivativeTable>
        <derivativeTransaction>
            <securityTitle>
                <value>Phantom Shares (2017 Grant)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F1"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-02-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
                <footnoteId id="F2"/>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>385</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F1"/>
                    <footnoteId id="F4"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F3"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F3"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Ordinary Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>385.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Performance Shares (2018 Grant)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-02-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>A</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F5"/>
                    <footnoteId id="F7"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>A</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F6"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F6"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Ordinary Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>7000</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
        <derivativeTransaction>
            <securityTitle>
                <value>Performance Shares (2018 Grant)</value>
            </securityTitle>
            <conversionOrExercisePrice>
                <footnoteId id="F5"/>
            </conversionOrExercisePrice>
            <transactionDate>
                <value>2019-02-15</value>
            </transactionDate>
            <transactionCoding>
                <transactionFormType>4</transactionFormType>
                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
            </transactionCoding>
            <transactionAmounts>
                <transactionShares>
                    <value>7000</value>
                </transactionShares>
                <transactionPricePerShare>
                    <footnoteId id="F5"/>
                    <footnoteId id="F7"/>
                </transactionPricePerShare>
                <transactionAcquiredDisposedCode>
                    <value>D</value>
                </transactionAcquiredDisposedCode>
            </transactionAmounts>
            <exerciseDate>
                <footnoteId id="F6"/>
            </exerciseDate>
            <expirationDate>
                <footnoteId id="F6"/>
            </expirationDate>
            <underlyingSecurity>
                <underlyingSecurityTitle>
                    <value>Ordinary Shares</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>7000.0</value>
                </underlyingSecurityShares>
            </underlyingSecurity>
            <postTransactionAmounts>
                <sharesOwnedFollowingTransaction>
                    <value>0</value>
                </sharesOwnedFollowingTransaction>
            </postTransactionAmounts>
            <ownershipNature>
                <directOrIndirectOwnership>
                    <value>D</value>
                </directOrIndirectOwnership>
            </ownershipNature>
        </derivativeTransaction>
    </derivativeTable>

    <footnotes>
        <footnote id="F1">Each Phantom Share represents the right to receive the economic equivalent of one of the Issuer's Ordinary Shares.</footnote>
        <footnote id="F2">This Form 4 is being filed as a result of the closing on February 15, 2019 of the merger (the &quot;Merger&quot;) as described in the Agreement and Plan of Merger, dated as of August 27, 2018 (the &quot;Merger Agreement&quot;) among Aspen Insurance Holdings Limited (the &quot;Issuer&quot;), Highlands Holdings, Ltd., and Highlands Merger Sub, Ltd.</footnote>
        <footnote id="F3">At the time of grant on February 10, 2017, the 2017 Phantom Shares were eligible for vesting following the achievement of certain financial targets by the Issuer. Prior to the Merger, one third of the 2017 Phantom Share award was tested annually over a three-year period. All vested 2017 Phantom Shares would have been settled in cash upon the filing of the annual report on Form 10-K for the year ended December 31, 2019. Two thirds of the 2017 Phantom Shares were forfeited based on the Issuer's 2017 and 2018 adjusted annual growth in diluted book value per ordinary share test and one third of the 2017 Phantom Shares vested at target payout levels in connection with the Merger.</footnote>
        <footnote id="F4">At the effective time of the Merger, each 2017 Phantom Share outstanding immediately prior to the Merger was, to the extent not vested, fully vested, and was canceled and converted into the right to receive a lump-sum amount in cash, equal to $42.75, without interest and less any applicable tax withholding, per 2017 Phantom Share.</footnote>
        <footnote id="F5">Each Performance Share represents the right to receive one share of the Issuer's Ordinary Shares.</footnote>
        <footnote id="F6">At the time of grant on February 9, 2018, the 2018 Performance Shares were eligible for vesting following the achievement of certain financial targets by the Issuer. Prior to the Merger, one third of the 2018 Performance Share award was tested annually over a three-year period. All vested 2018 Performance Shares would have been issued following the filing of the annual report on Form 10-K for the year ended December 31, 2020. One third of the 2018 Performance Shares were forfeited based on the Issuer's 2018 adjusted annual growth in diluted book value per ordinary share test and two thirds of the 2018 Performance Shares vested at target payout levels in connection with the Merger.</footnote>
        <footnote id="F7">At the effective time of the Merger, each 2018 Performance Share outstanding immediately prior to the Merger was, to the extent not vested, fully vested, and was canceled and converted into the right to receive a lump-sum amount in cash, equal to $42.75, without interest and less any applicable tax withholding, per 2018 Performance Share.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/Silvia Martinez as Attorney-in-fact for Heather Brown</signatureName>
        <signatureDate>2019-02-20</signatureDate>
    </ownerSignature>
</ownershipDocument>
</XML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>poa.htm
<DESCRIPTION>POWER OF ATTORNEY FOR: /S/SILVIA MARTINEZ AS ATTORNEY-IN-FACT FOR HEATHER BROWN
<TEXT>
<!-- Document created using Workiva -->
<html>
<body>
<pre>
Power of Attorney Relating to Section 16 Filings

Know all by these presents, that the undersigned hereby constitutes and appoints each of Michael Cain, Silvia Martinez, Debra Collins and Ella Crawley with full power of substitution and resubstitution, the undersigned's true and lawful attorney-in-fact to:

(1) prepare, execute in the undersigned's name and on the undersigned's behalf, and submit to the U.S. Securities and Exchange Commission (the "SEC") a Form ID, including amendments thereto, and any other documents necessary or appropriate to obtain codes and passwords enabling the undersigned to make electronic filings with the SEC of reports required by Section 16(a) of the Securities Exchange Act of 1934, as amended (the "Exchange Act") or any rule or regulation of the SEC;

(2) execute for and on behalf of the undersigned, in the undersigned's capacity as an officer and/or director of Aspen Insurance Holdings Limited (the "Company"), any Form 3, 4, and 5 in accordance with Section 16(a) of the Exchange Act;

(3) prepare and sign on behalf of the undersigned any Form 144 Notice under the Securities Act of 1933, as amended (the "Securities Act"), and file the same with the SEC;

(4) do and perform any and all acts for and on behalf of the undersigned which may be necessary or desirable to complete and execute any such Form 3, 4, 5, or 144, complete and execute any amendment or amendments thereto, and timely file such form with the SEC and any stock exchange or similar authority; and

(5) take any other action of any type whatsoever in connection with the foregoing which, in the opinion of such attorney-in-fact, may be of benefit to, in the best interest of, or legally required by, the undersigned, it being understood that the documents executed by such attorney-in-fact on behalf of the undersigned pursuant to this Power of Attorney shall be in such form and shall contain such terms and conditions as such attorney-in-fact may approve in such attorney-in-fact's discretion.

The undersigned hereby grants to each such attorney-in-fact full power and authority to do and perform any and every act and thing whatsoever requisite, necessary, or proper to be done in the exercise of any of the rights and powers herein granted, as fully to all intents and purposes as the undersigned might or could do if personally present, with full power of substitution or revocation, hereby ratifying and confirming all that such attorney-in-fact, or such attorney-in-fact's substitute or substitutes, shall lawfully do or cause to be done by virtue of this power of attorney and the rights and powers herein granted. The undersigned acknowledges that the foregoing attorneys-in-fact, in serving in such capacity at the request of the undersigned, are not assuming, nor is the Company assuming, any of the undersigned's responsibilities to comply with Section 16 of the Exchange Act or Section 5 of the Securities Act or Rule 144 promulgated under such Act.

This Power of Attorney shall remain in effect until the undersigned is no longer required to file Forms 3, 4, 5 and 144 with respect to the undersigned's holdings of and transactions in securities issued by the Company, unless earlier revoked by the undersigned in a signed writing delivered to the foregoing attorneys-in-fact.

IN WITNESS WHEREOF, the undersigned has hereunto set his hand this 25 day of September, 2017.

/s/Heather Brown


Heather Brown
</pre>
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</SEC-DOCUMENT>
