Chrome's third-party cookie deprecation trials: changes to the grace period

From July 1, 2024, sites and services that have registered for one of the third-party cookie deprecation trials will receive a grace period of 60 days to deploy trial tokens, starting from the date their trial registration was approved.

During this time, the site or service will continue to be able to access third-party cookies for non-ads use cases.


To ensure sites have enough time to migrate away from third-party cookie dependencies, Chrome has provided first-party and third-party deprecation trials to temporarily re-enable cookies for non-ads use cases.

In addition, while sites apply for and deploy tokens for the deprecation trials, Chrome implemented a grace period to temporarily re-enable third-party cookies for sites with reported user-facing breakage. During the grace period, origins registered for a deprecation trial can access third-party cookies in Chrome even if they have not yet deployed trial tokens. The grace period was scheduled to end on June 30, 2024. In light of the most recent update on the plan for phase-out of third party cookies, Chrome will continue the grace period on a rolling basis.

Details of the updated grace period

  • Sites and services that are approved for a deprecation trial on or after July 1st will receive a 60-day grace period starting from the date the registration was approved.
  • Sites and services that were approved for one of the deprecation trials before July 1, 2024 will be granted an automatic one-time grace period extension of 60 days, to August 30, 2024.
  • Origins that were added to the grace period after reporting breakage but have not yet applied to a deprecation trial should apply for a deprecation trial as soon as possible to ensure continued access to the grace period. The grace period will lapse on June 30 for sites on the grace period that have not been approved for a deprecation trial.

This applies to both the first and third-party deprecation trials, which are scheduled to end on December 27, 2024. Chrome intends to revise this end date and will announce any changes in the Privacy Sandbox developer blog.

We encourage sites and services to implement deprecation trial tokens as quickly as possible to allow for more fine-tuned testing of third-party cookie deprecation readiness. The grace period and deprecation trials are available for sites and services that meet the eligibility criteria. To preserve access to third-party cookies, participating origins must deploy deprecation trial tokens before the extended grace period expires.

Preserving critical user experiences provides more information about the third-party cookie deprecation trials.