Impact of AI Search Summaries on Website Traffic: Evidence from Google AI Overviews and Wikipedia

A recent research study examining Google's AI Overviews (AIO) found that the introduction of AI-generated answers in search results significantly reduced traffic to informational publishers. Specifically, the study observed a 4.82% to 5.45% decrease in external search referrals to English Wikipedia articles following the default availability of AIO.

Why it matters

This research highlights a significant shift in how information is consumed, with AI-powered search features acting as a new intermediary that can divert substantial user traffic from content creators. This has direct implications for business models reliant on digital traffic and advertising revenue, as well as the broader ecosystem of online content creation and dissemination. Organizations must consider how AI-driven search changes discoverability and engagement with their online presence.

Key insights

• Search engines are increasingly integrating AI-generated answers directly into search results, positioned above traditional organic links.
• This integration has the potential to redirect user attention and traffic away from original content publishers.
• A study using a difference-in-differences design compared English Wikipedia traffic with German and French versions following AIO's staggered geographic rollout.
• The default availability of Google's AI Overviews (AIO) led to a reduction in English Wikipedia's search traffic by 5.45% when compared to German Wikipedia, and 4.82% when compared to French Wikipedia.
• The findings suggest that digital intermediaries producing AI answers can substantially reallocate user attention from original informational sources.

Source

arXiv — Computers and Society — https://arxiv.org/abs/2602.18455