Navigating the Waves of Change: Google’s Recent Algorithm Updates Explained For Marketing Agencies | Client Education Resource
The last few months have been one of the most volatile periods in SEO in recent memory. Google launched two major algorithm updates — one in December 2025 and one in February 2026 — that reshuffled rankings across virtually every industry. If your clients have been asking why their traffic changed, here is everything you need to know. Update #1: The December 2025 Core Update (“The Core Before Christmas”) Rollout Period: December 11 – December 29, 2025 (18 days) Type: Broad Core Update — affects all of Google Search Scale: One of the most significant updates of 2025, following smaller “mini-core” updates throughout the fall that foreshadowed it. This was Google’s third and final broad core update of 2025, and it hit hard — right in the middle of the holiday season. Nearly 15% of pages that ranked in the Top 10 before the update disappeared entirely from the Top 100 by the time it finished rolling out. What Google Changed:... Who Won and Who Lost: Update #2: The February 2026 Discover Core Update Rollout Period: February 5 – February 27, 2026 (22 days) Type: Discover-Specific Core Update — affects Google Discover only, NOT traditional search rankings Scale: Unprecedented — this is the first time Google has ever issued a standalone core update targeting Discover independently from Search. Google Discover is the personalized content feed that surfaces articles on mobile devices and the Google app — without users ever typing a search query. This update was a complete overhaul of how Discover selects and surfaces content, and it signals that Google now considers Discover’s quality systems entirely separately from Search. What Google Changed in Discover: “This is not a standard core update. It is a standalone algorithmic overhaul of how Discover selects and surfaces content.” — Affiverse Media The Bigger Picture: Volatility Has Not Stopped It is important for your clients to understand that ranking volatility did not end when these updates completed. Google has continued pushing what the SEO community calls “smaller core updates” — unconfirmed algorithmic adjustments that Google does not officially announce — throughout January and into March 2026. Tools like Semrush, Sistrix, and others have been registering near-daily elevated volatility signals since December.