Google is auto-migrating older Search campaigns to AI Max through September and Microsoft is removing the Max CPC cap from new automated campaigns from October. Both moves strip manual controls from advertisers and hand more of the decision to the platform. Australian advertisers get no local opt-out, so the time to audit accounts is now.
The Take: Two of the biggest search advertising platforms spent this month quietly taking manual levers off the table. Google is auto-migrating older Search campaigns to its AI Max system through September and Microsoft is removing the Max CPC cap from new automated campaigns from October. This is not a bidding tweak. It is a transfer of control from the advertiser to the machine.
The rollout: From 1 September Google began automatically upgrading Search campaigns that use Campaign-level Broad Match or standalone Automatically Created Assets to AI Max, rolling out gradually across the month. Since 3 August advertisers can no longer build those legacy structures at all, in the interface or the API. Dynamic Search Ads get a stay until February 2027, so the squeeze arrives in stages rather than all at once.
The mechanics: Microsoft is moving the same way. Microsoft Advertising will stop letting advertisers set a Max CPC on new standalone Max Conversion, Max Conversion Value and Max Click campaigns from 1 October, on the argument that a manual cap can override the performance goal the advertiser set. Existing campaigns and portfolio strategies keep the field for now, which tells you where this is heading.
Australian search ad spend in FY26, the money these automation changes now sit on top of
The trade-off: These systems often lift conversions and Google says campaigns migrate in place with equivalent settings. The cost is visibility. Broad match plus automated assets plus automated bidding means the platform decides more of what your budget chases, and the levers to rein it back are disappearing one release at a time. When the account underperforms, you will have fewer places to reach in and fix it.
For Australian operators: Australian advertisers get no local opt-out, and search is the largest slice of the country's record 19.8 billion dollar ad market. Before the auto-migration reaches your account, list every campaign still on broad match or automated assets and decide which ones you actually want to hand over. Set a target CPA or ROAS and a firm budget, because those become your main controls once the manual cap is gone. Read the search terms report every week, since broad match with no cap is where wasted spend hides.