Google has begun rolling out its December 2025 Core Update, making it the third major core update of the year. The rollout started on December 11, 2025, at 9:25 a.m. Pacific Time and is expected to take up to three weeks to fully complete.
The update was officially confirmed on Google’s Search Status Dashboard, where it has been categorized as an “incident affecting ranking.” This follows Google’s earlier core updates released in March and June 2025.
What This Update Means
Core updates involve wide-ranging adjustments to Google’s ranking systems with the goal of improving the overall quality and relevance of search results. Unlike updates that focus on spam prevention or specific ranking factors, core updates impact how content is evaluated and ranked across the web.
During the rollout period, website owners and SEO professionals may notice temporary fluctuations in search rankings as Google’s systems reprocess content under the updated framework.
Core Updates in 2025: A Quick Timeline
The December 2025 core update follows two major algorithm updates released earlier this year.
The March 2025 core update ran from March 13 to March 27, completing its rollout in about two weeks. SEO tracking tools reported ranking volatility comparable to what was seen during the December 2024 core update.
The June 2025 core update was rolled out between June 30 and July 17, lasting roughly 16 days. According to industry data, it was considered one of the more significant core updates in recent years. During this period, some websites impacted by the September 2023 Helpful Content Update experienced partial visibility recoveries.
Google Updates Guidance on Ongoing Algorithm Changes
Just two days ahead of the December rollout, Google revised its core updates documentation, adding new wording around continuous algorithm adjustments.
Google clarified that meaningful improvements to content can result in ranking changes even outside officially announced core updates, reflecting the company’s ongoing refinement of its ranking systems.
Why This Is Important
If your site experiences ranking fluctuations in the coming weeks, the December core update is likely playing a role.
Core updates often reshuffle search results for pages that haven’t violated any guidelines. Google has repeatedly emphasized that a drop in rankings does not automatically mean there is something wrong with a page. Instead, the update reflects how content is being re-evaluated in comparison to other available results.
The recent documentation update reinforces that ranking shifts can occur between major updates, as Google continues to roll out smaller, unannounced changes behind the scenes.
Looking Ahead
Google will announce the completion of the rollout through its Search Status Dashboard once the update has fully finished.
Over the next two to three weeks, it’s important to keep a close eye on your search rankings and website traffic. If you notice any shifts, note the timing and compare it with the rollout timeline to better understand the impact.
Based on the pattern of core updates released in 2025, the rollout is expected to take several weeks. Google will officially confirm its completion via the dashboard and through updates shared on its Search Central social channels.