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Heads upKlaviyo · Data · Tue, Sep 1, 2026
First-Party ID extends Klaviyo's cookie window on Safari from 24 hours to 7 days
What changed
First-Party ID helps Klaviyo recognize returning visitors on Safari and other restrictive browsers by extending its cookie window from 24 hours to 7 days. It requires setup.
What to do
Set it up. More identified visitors means more browse and cart abandonment triggers.
Source
← New Automatic Events setting lets AI add and manage standard events on your siteGoogle Ads API v22 sunset on Oct 7 →
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