
Key takeaways
- Google pre-announced the update on 3 December 2020 and it went live later that day.
- Google said on 16 December 2020 that the rollout was complete.
- Google said at launch that such updates typically take about one to two weeks to roll out.
- It was the first confirmed core update since May 2020, seven months earlier.
What Google changed
On the morning of 3 December 2020 Google SearchLiaison posted: “Later today, we are releasing a broad core algorithm update, as we do several times per year. It is called the December 2020 Core Update.” Google gave no detail on what changed and linked to its standing guidance on core updates.
When it rolled out
Later on 3 December 2020, Google SearchLiaison posted that the update was “now rolling out live” and would typically take about one to two weeks. Search Engine Roundtable put the start at about 1pm Eastern time. On 16 December 2020 Google posted: “The December 2020 Core Update rollout is complete.”
Search Engine Roundtable reported that tracking tools showed most of the movement on 4 December and a second wave around 10 December, with little change in between.
What is known about its impact
Google published no impact figures for this update. Its core update guidance says these updates “don’t target specific sites or individual web pages,” and that pages which move down are not necessarily bad; other pages may simply serve the searcher better. Treat any winner or loser percentage attributed to this update as a third-party estimate.
What site owners should do
Google’s core ranking systems are still in use today, and its current core update guidance applies to this update as much as to recent ones:
- Wait until a core update has finished, then at least one more full week, before judging.
- Compare a week after the update with a week before it began.
- Take no drastic action for small drops; for a large, sustained drop, assess the whole site against Google’s helpful content self-assessment questions.
- Expect recovery, if it comes, to take time and often a later core update.
How to check whether it affected you
Search Console keeps only 16 months of data, so its reports no longer cover December 2020. Use archived analytics exports and compare the week before 3 December with the week starting 23 December. Holiday demand distorts late December, so check the same weeks in other years too. The Google Algorithm Updates timeline lists the updates around it.
Related updates
- The May 2020 core update was the previous core update.
- The June 2021 core update was the next one.
The evidence
- Type
- core update
- Started
- 3 December 2020
- Completed
- 16 December 2020
- Confirmed by
- Google statement
Sources
- 1.The December 2020 Core Update is now rolling out live - Google SearchLiaison on X, December 3, 2020Primary
- 2.Later today, we are releasing a broad core algorithm update - Google SearchLiaison on X, December 3, 2020Primary
- 3.The December 2020 Core Update rollout is complete - Google SearchLiaison on X, December 16, 2020Primary
- 4.Google December 2020 core update is now live - Search Engine Roundtable, December 4, 2020
- 5.Google December 2020 core update is completely rolled out - Search Engine Roundtable, December 17, 2020
- 6.Google Search's core updates and your website - Google Search CentralPrimary
Frequently asked questions
When did the December 2020 core update start and finish?
Google SearchLiaison posted on 3 December 2020 that it was rolling out live, and on 16 December 2020 that the rollout was complete.
Why was the December 2020 core update released before the holidays?
Google did not give a public reason. Search Engine Roundtable reported that many SEOs felt the timing was poor, and that Google considered it acceptable because it came after Black Friday and Cyber Monday.
How long after the previous core update did it come?
The previous confirmed core update started on 4 May 2020, so there were seven months between the two confirmed core updates.
What should I do if the December 2020 core update hurt my site?
Google's guidance is that a core update drop does not mean a page broke a rule. Compare traffic before and after, and if the drop is large and sustained, assess the site against Google's helpful content questions.
About the author

Founder, UpgradIQ FZC LLC
Adam Hafez works on technical SEO and search measurement: how pages get crawled, indexed, ranked and now quoted by answer engines. He founded UpgradIQ, which reads Google Search Console and GA4 to tie ranking movement back to the changes that caused it. He publishes what the data supports and states the limits of it.
- Technical SEO
- Search Console and GA4 measurement
- Answer engine optimization
- Structured data
The briefing
Only what actually changed in search, delivered in full by RSS, Atom or JSON feed.
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