AI Overview Impact on CTR: An Analytical Report (October 2024 vs. May 2025)

From October 2024 to May 2025, Google’s AI Overviews went from a limited experiment to a default fixture of the search results page for millions of questions. For SEO teams, this eight-month window provides the cleanest real-world proof yet of how generative, on-SERP answers are reshaping click-through rate (CTR) — and, by extension, organic traffic. This report breaks down how fast AI Overviews spread, what happened to CTR as a result, and what it means for brands still depending on organic search to drive visits.

How Fast AI Overviews Spread

The growth curve during this period was steep by any measure, even if trackers won’t agree on the exact figures because everyone uses a different keyword sample and methodology. Early trackers had Semrush placing AI Overview presence at roughly 2% of desktop questions in late September 2024 whereas BrightEdge recorded appearances in around 8% of keywords that same summer and SE Ranking measured a higher 12.47% across a 1,00,000-keyword sample in September 2024.
By the end of 2024, the trend accelerated sharply. SE Ranking recorded AI Overviews appearing in 18.76% of US SERPs by November 2024, up from 7.47% just four months earlier in July. Momentum carried into the following spring – Semrush data showed AI Overviews triggering on 13.14% of all US desktop questions by March 2025, a 102% jump from 6.49% in January 2025 alone.

Whichever tool you trust, the direction is unambiguous — AI Overview coverage roughly doubled, tripled or more within the Oct 2024 – May 2025 window, moving the feature from a niche curiosity to something most searchers now encounter regularly.

The Core AI Overview CTR Study

The most rigorous public data on AI Overviews CTR comes from Ahrefs, whose study spans almost exactly this window. Analyzing 300,000 keywords — split evenly between informational queries with and without an AI Overview — Ahrefs found that the presence of an AI Overview correlated with a 34.5% lower average clickthrough rate for the top-ranking organic page compared to similar informational keywords without one. This is one of the largest independent datasets published on the topic, and it directly contradicts Google’s own public position that AI Overviews increase engagement with cited sources.

The position-one numbers make the AI Overview traffic drop tangible. Comparing March 2024 (before the US rollout) to March 2025, the average position-one CTR for informational keywords fell from 5.6% down to 3.1% — nearly halved in a single year. And critically, Ahrefs’ research found that 99.2% of keywords triggering AI Overviews were informational in intent, which explains why “how,” “what,” and “why” queries absorbed the brunt of the impact while commercial and transactional searches were largely spared during this period.

The Trend Didn’t Stop in May 2025

It’s valuable to note where this trajectory is going next, since it confirms the Oct 2024 – May 2025 period was the beginning of a bigger slide rather than a one-off dip. When Ahrefs re-ran the same study later, the CTR fine for position one had deepened to 58% by December 2025, with minor but still sound drops recorded across every position down to tenth. That later finding was corroborated by independent researchers – Seer Interactive measured organic CTR declines between 49.4% and 65.2%, Kevin Indig reported drops going beyond 50% and Authoritas found a 47.5% reduction. The May 2025 figures, in other words, were not the floor — they were a midpoint in an ongoing decline.

What Changed at the Position Level

A consistent pattern across every dataset from this era is that the effect isn’t evenly distributed. The higher a page ranks, the more clicks it stands to lose, because AI Overviews sit directly above position one and intercept the searcher’s attention before they ever scroll to the organic listings. Position one pages, historically the biggest CTR winners on any SERP, ended up being the biggest losers in relative terms once an AI Overview appeared above them. Lower positions had less CTR to lose in the first place, so their percentage declines — while still real — were comparatively smaller.

What this Means for SEO Strategy

The AI Overview impact on SEO during this period wasn’t uniform, and neither should the response be:

1. Treat informational content as a visibility play, not just a traffic play – With most AI Overviews triggering on “know” queries, ranking #1 no longer guarantees a click the way it once did. Success metrics need to expand beyond CTR to include whether your brand is being cited inside the AI Overview itself.
2. Structure content to be extractable – Clear, direct answers near the top of the page, question-based subheadings, and well-supported facts make it easier for Google’s AI to lift and cite your content — turning an “impression without a click” into a brand mention that still builds trust.
3. Defend transactional and commercial keywords – These queries were the safest zone during the Oct 2024–May 2025 window, since AI Overviews appeared on them far less often. That gap is narrowing, but for now, ranking #1 on high-intent commercial terms still delivers reliable clicks.
4. Keep monitoring, not just optimizing – Given how quickly prevalence and CTR impact both moved within eight months, static strategies age fast. Continuous tracking of AI Overview trigger rates for your distinct keyword set is now a baseline SEO task, not an occasional audit.

Conclusion

The data from October 2024 to May 2025 tells a consistent story: AI Overviews expanded rapidly, informational CTR fell sharply as a direct result, and the position-one advantage that organic SEO was built around started eroding in real time. For brands relying on organic informational content, the priority is shifting from “rank first” to “be the source the AI cites” — a change in strategy, not just tactics.

At Web Spider Solutions, we assist brands adapt their SEO and content strategy to this shift, from technical optimization to AI/answer-engine visibility. In case you’re looking for your own CTR trends to move in this direction, it’s worth a closer look at how your content is positioned for both classic rankings and AI-generated answers.

FAQs

What is the AI Overview influence on CTR between October 2024 and May 2025?

Throughout this period, AI Overview presence in US search results grew several-fold and independent research from Ahrefs found this correlated with a 34.5% lower average CTR for top-ranking organic pages on impacted questions.

Which kinds of questions were hit hardest by AI Overviews?

Informational “know” questions (how, what, why) saw the steepest CTR declines, since roughly 99.2% of keywords triggering AI Overviews are informational in intent. Transactional and commercial searches were highly unaffected during this window.

Did the #1 ranking position loses the most clicks?

Yes. Position one lost the biggest share of clicks in relative terms as AI Overviews appear directly above it, intercepting focus before searchers reach the organic listings below.

Has the AI Overview CTR fall gotten worse since May 2025?

It has. Later Ahrefs data showed the position-one CTR penalty deepening to 58% by December 2025, corroborated by separate studies from Seer Interactive and Authoritas — suggesting May 2025 was a midpoint, not the endpoint.

How should brands respond to the AI Overviews traffic drop?

Shift some KPIs from clean CTR to AI citation visibility, structure content for easy extraction (clear answers, FAQ formatting, strong E-E-A-T signals) and continue prioritizing transactional keywords where organic clicks remain more dependable.