    <SEC-DOCUMENT>0001628280-23-031916-index.html : 20230911
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    <ACCEPTANCE-DATETIME>20230911060520
    ACCESSION NUMBER:		0001628280-23-031916
    CONFORMED SUBMISSION TYPE:	S-1/A
    PUBLIC DOCUMENT COUNT:		29
    FILED AS OF DATE:		20230911
    DATE AS OF CHANGE:		20230911

    FILER:

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

    	FILING VALUES:
    		FORM TYPE:		S-1/A
    		SEC ACT:		1933 Act
    		SEC FILE NUMBER:	333-274211
    		FILM NUMBER:		231246579

    	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
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    <SEQUENCE>1
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    Document 2 - file: exhibit107-sx1a.htm

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    Document 4 - file: exhibit51-sx1a.htm

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    <FILENAME>business10a.jpg
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    Document 11 - file: business13a.jpg

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    Document 15 - file: business4a.jpg

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    Document 16 - file: business4b.jpg

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    Document 24 - file: covertart3b.jpg

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    Document 25 - file: deloittelogo.jpg

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    Document 28 - file: mda1b.jpg

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