topic
Verified 2026-09-18

Partitioned Cookies (CHIPS)

Partitioned cookies keep third-party state separated by the top-level site that embeds it.

Use Partitioned only for a genuine cross-site embedded use case and pair it with Secure. Partitioning reduces cross-site tracking and changes how integrations find their state.

httpcookiesprivacysecuritybrowser

Reference (http)

Set-Cookie: widget_session=abc; Secure; HttpOnly; SameSite=None; Partitioned

Use Partitioned only for a genuine cross-site embedded use case and pair it with Secure. Partitioning reduces cross-site tracking and changes how integrations find their state.

Common mistakes

  • Treating Partitioned as a general replacement for SameSite or assuming all browsers and server-side clients support it.
Permalink: https://merginit.com/reference/http/cookie-partitioned