Starting March 2026, Lookalike audiences in Demand Gen will no longer act as strict targeting constraints.
Instead of targeting only users within the selected similarity threshold (narrow, balanced, broad), Google will use Lookalike as a signal. The system can expand beyond the defined audience if it predicts better conversion performance or lower CPA.
This is similar to Optimized Targeting, but it does not replace it. When combined, expansion can go even further.
Advertisers who want to keep legacy Lookalike as a hard constraint will need to request it via a form.
Another step toward AI-led targeting similar to Meta’s direction in recent years.
Thanks for sharing Dario Zannoni
