Integration and Competition in Generative AI: Evidence from Google’s AI Mode Rollout

Integrating generative AI into digital platforms may reshape competition among AI assistants. We study whether Google’s introduction of AI Mode within Search reduces traffic to competing services. We exploit the August 2025 expansion of Google’s AI Mode, which reached 25 sample countries, using website traffic estimates for ten AI assistants and a difference-in-differences design with 30 countries where AI Mode was unavailable. Making AI Mode available within Google Search reduced ChatGPT website visits by 5.9 percent over the first four weeks, implying 3.5 million fewer daily visits across treated countries. The decline is concentrated in direct visits, while organic-search referrals change little. Daily unique visitors decline by a similar proportion, with little change in visits per daily visitor or average visit duration, suggesting the reduction primarily reflects lower daily reach. Point estimates remain negative throughout the 40-day follow-up, after which comparison countries also gain access to AI Mode. We find no statistically significant average effect on Gemini or the eight smaller assistants combined over the first four weeks. These findings suggest integrating conversational AI into established search interfaces can reduce traffic to standalone competitors, highlighting distribution channels’ importance for competition among AI assistants.