The Third-Party Cookie Phase-Out Timeline: What Changed and What Didnt
PB
Patrick Bushe
February 1, 2025 · 5 min read
For five years, the web expected Chrome to drop third-party cookies, the main way advertisers tracked people across sites. It never happened. Here's what Google planned, what changed, and where things stand.
The timeline
- January 2020: Google announces it will phase out third-party cookies in Chrome within two years, replaced by "Privacy Sandbox" tools for advertising.
- March 2020: Safari blocks all third-party cookies by default. Firefox was already blocking known trackers' cookies.
- June 2021: Google delays the plan to late 2023.
- June 2022: Firefox turns on Total Cookie Protection for all users, giving each site its own separate cookie jar.
- July 2022: Google delays again, to the second half of 2024.
- January 4, 2024: Chrome blocks third-party cookies for one in every hundred users as a test.
- April 2024: another delay, partly over concerns from the UK's competition regulator.
- July 2024: Google drops the plan and proposes letting users choose instead.
- April 2025: Google says it won't show a new choice prompt either. Third-party cookies stay on by default, with blocking available in settings.
- October 2025: Google retires most Privacy Sandbox advertising features, including the Topics API.
What changed
- Safari and Firefox users have had strong cookie protection for years.
- Chrome users can block third-party cookies in Settings → Privacy and security → Third-party cookies. Incognito blocks them by default.
- Advertisers moved toward first-party data, logins, and other tracking methods. See first-party vs third-party cookies.
- Some Privacy Sandbox pieces survived, such as partitioned cookies (CHIPS) and FedCM for sign-ins.
What didn't change
- Most Chrome users still have third-party cookies on.
- Cookie consent banners are still required in the EU and UK, whatever browsers do.
- Tracking without cookies, such as fingerprinting and bounce tracking, kept growing. See fingerprinting and bounce tracking.
What you can do
- Block third-party cookies in Chrome's settings.
- Reject non-essential cookies on banners. Cookie Auto-Reject clicks "Reject all" for you on many sites.
- Clear cookies regularly.
- Work through a full Chrome privacy checklist.
Why the plan kept slipping
Advertisers and publishers argued the replacement tools weren't ready and would cut their income. Regulators worried that removing cookies while Google kept its own data would strengthen Google's ad business. Each delay came after pressure from one or both, and in the end Google kept cookies rather than settle those arguments.
See also what the Privacy Sandbox was.
