Google September 2026 Spam Update: A 13-Day, 16-Hour Timeline
Google released the September 2026 spam update on September 24, 2026 and marked it complete on October 8. The rollout took 13 days 16 hours. It was the fourth spam update of 2026 and the first one this year to run longer than three days. The earlier three took 19.5 hours, 2 days 1 hour and 2 days 16 hours.
Where the first three spam updates of the year each wrapped up within three days, this one ran for nearly two weeks in three distinct waves. Mid-rollout, Google also revised its generative AI content guide and added a “main content” definition and a fake-author clause to the helpful content page. If your site lost traffic between late September and early October, the two easiest mistakes to make are treating the September 26 rank-tracker scraping glitch as a real demotion, and overhauling your whole site for a core update when an algorithmic filter only hit one templated directory.