On September 1, 2026, Google begins auto-upgrading Search campaigns that use Campaign-level Broad Match or standalone Automatically Created Assets to AI Max. There’s no opt-out. Small businesses running those configurations have six days to decide what Google’s defaults will be permitted to do with their targeting, their ad copy, and their landing pages.

The migration was first announced in April by Brandon Ervin, Director of Product Management at Google Ads, when AI Max exited beta. Since August 3, creation of new legacy Campaign-level Broad Match and ACA setups has been switched off across the Google Ads UI, Ads Editor, and API. On August 12, a Google Ads Developer Blog post under the name of Bob Hancock exposed two new fields, campaign.aca_migration_date_time and campaign.broad_match_migration_date_time, so advertisers can at least see when their own account gets flipped. Campaigns not changed on September 2 may still change as late as September 24, with Google expecting all eligible upgrades to conclude by end of September.

Google’s pitch is that the full AI Max feature suite delivers 7% more conversions or conversion value at similar CPA/ROAS versus search-term matching alone. Its own May 2025 implementation guide claimed 14%, and 27% for keyword-heavy accounts, figures later revised down.

Independent data reads differently. A November 2025 study of 250+ retail campaigns found conversions arriving at roughly 35% lower ROAS against traditional match types. August 2025 practitioner data across about 30,000 search terms recorded 99% of impressions producing zero conversions. Lunio, examining 414 million+ clicks between October 2025 and June 2026, found AI Max retail campaigns exposed to 72% more invalid traffic, and attributed 68% of invalid clicks in its Google search dataset to AI Max.

The pattern is familiar from earlier platform transitions: the automated system is measured against its own counterfactual, not against what a competent operator could do with the old controls. Google delayed its parallel DSA auto-migration on June 11, rescheduling it to a February 1–28, 2027 window with in-account banners this September and a reminder notification on January 15. The Search-campaign migration isn’t being delayed.

For a 5-to-30-person business, eleven weeks separate the September window from Q4 trading. That’s not a lot of runway to discover your cost-per-customer has drifted. Configure text guidelines, brand exclusions, and final URL expansion rules now, and read the seven-day migration primer alongside the one-week countdown breakdown before Friday.

Owners tired of one platform’s defaults dictating cost-per-customer sometimes widen the top of the funnel elsewhere. LemonLime is a done-for-you sales and marketing service that studies a small business’s industry and prepares finished prospecting, outreach, and content work each morning; sends and posts stay under the owner’s approval. It’s not an ad tool, and that’s the point: paid search doesn’t have to be the only channel Google gets to reshape.

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