<SEC-DOCUMENT>0001835830-25-000060.txt : 20250516
<SEC-HEADER>0001835830-25-000060.hdr.sgml : 20250516
<ACCEPTANCE-DATETIME>20250516205946
ACCESSION NUMBER:		0001835830-25-000060
CONFORMED SUBMISSION TYPE:	4
PUBLIC DOCUMENT COUNT:		1
CONFORMED PERIOD OF REPORT:	20250514
FILED AS OF DATE:		20250516
DATE AS OF CHANGE:		20250516

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Bialecki Andrew
		CENTRAL INDEX KEY:			0001991099
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		4
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-41806
		FILM NUMBER:		25961292

	MAIL ADDRESS:	
		STREET 1:		KLAVIYO, INC.
		STREET 2:		125 SUMMER STREET, 6TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			Klaviyo, Inc.
		CENTRAL INDEX KEY:			0001835830
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-PREPACKAGED SOFTWARE [7372]
		ORGANIZATION NAME:           	06 Technology
		EIN:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		125 SUMMER STREET, FLOOR 6
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
		BUSINESS PHONE:		800-338-1744

	MAIL ADDRESS:	
		STREET 1:		125 SUMMER STREET, FLOOR 6
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02110
</SEC-HEADER>
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<TYPE>4
<SEQUENCE>1
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<DESCRIPTION>FORM 4
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        <issuerTradingSymbol>KVYO</issuerTradingSymbol>
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            <rptOwnerStreet2>125 SUMMER STREET, 6TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02110</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
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            <isOfficer>1</isOfficer>
            <isTenPercentOwner>1</isTenPercentOwner>
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            <officerTitle>Chief Executive Officer</officerTitle>
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                <directOrIndirectOwnership>
                    <value>D</value>
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            <securityTitle>
                <value>Series B Common Stock</value>
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            <exerciseDate>
                <footnoteId id="F3"/>
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                    <footnoteId id="F5"/>
                </natureOfOwnership>
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        <derivativeHolding>
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                    <value>By The Elizabeth L. Bialecki Irrevocable GST Trust of 2023</value>
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                    <value>By The Andrew P. Bialecki Irrevocable GST Trust of 2023</value>
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                </natureOfOwnership>
            </ownershipNature>
        </derivativeHolding>
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            <securityTitle>
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                </sharesOwnedFollowingTransaction>
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                <directOrIndirectOwnership>
                    <value>I</value>
                </directOrIndirectOwnership>
                <natureOfOwnership>
                    <value>By spouse</value>
                </natureOfOwnership>
            </ownershipNature>
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    <footnotes>
        <footnote id="F1">Represents shares of the Issuer's Series A Common Stock, par value $0.001 per share (&quot;Series A Common Stock&quot;), sold in an underwritten registered offering, the proceeds of which were used to satisfy taxes incurred in connection with stock option exercises.</footnote>
        <footnote id="F2">The shares underlying this option were fully vested and exercisable by the Reporting Person as of the date exercised.</footnote>
        <footnote id="F3">Each share of the Issuer's Series B Common Stock, par value $0.001 per share (&quot;Series B Common Stock&quot;), is convertible at any time at the option of the holder into one share of Series A Common Stock and will automatically convert into Series A Common Stock upon the occurrence of certain events as set forth in the Issuer's certificate of incorporation. The Series B Common Stock has no expiration date.</footnote>
        <footnote id="F4">Reflects 4,054,170 shares of Series B Common Stock previously transferred from the Andrew P. Bialecki Grantor Retained Annuity Trust I of 2023 to the Reporting Person.</footnote>
        <footnote id="F5">Shares held by the Andrew P. Bialecki Grantor Retained Annuity Trust I of 2023, of which the Reporting Person serves as trustee. The Reporting Person disclaims Section 16 beneficial ownership of such shares except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed to be an admission that he has beneficial ownership of such shares for Section 16 or any other purpose.</footnote>
        <footnote id="F6">Shares held by the Elizabeth L. Bialecki Irrevocable GST Trust of 2023, of which the Reporting Person serves as trustee. The Reporting Person disclaims Section 16 beneficial ownership of such shares except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed to be an admission that he has beneficial ownership of such shares for Section 16 or any other purpose.</footnote>
        <footnote id="F7">Shares held by the Andrew P. Bialecki Irrevocable GST Trust of 2023, of which the Reporting Person's spouse serves as trustee. The Reporting Person disclaims Section 16 beneficial ownership of such shares except to the extent of his pecuniary interest therein, if any, and this report shall not be deemed to be an admission that he has beneficial ownership of such shares for Section 16 or any other purpose.</footnote>
    </footnotes>

    <remarks></remarks>

    <ownerSignature>
        <signatureName>/s/ Landon Edmond, Attorney-in-Fact</signatureName>
        <signatureDate>2025-05-16</signatureDate>
    </ownerSignature>
</ownershipDocument>
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</SEC-DOCUMENT>
