Last updated: September 2026

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⚡ TL;DR
Google began automatically migrating campaign-level Broad Match and legacy Automatically Created Assets Search campaigns to AI Max on September 1, 2026, with no opt-out once the window closes, according to Search Engine Land and Search Engine Roundtable. Microsoft rolled out its own AI Max, on by default for new Search campaigns. Meanwhile, Smartly’s 2026 Digital Advertising Trends Report found marketers estimate roughly 20% of digital ad spend is wasted, even as 46% now use AI to scale creative. This piece explains exactly what changes, why now, and how to protect campaign performance during the transition.

Google’s AI Max Migration: What the Mandatory September 2026 Search Campaign Upgrade Means for Advertisers

If you manage Google Search campaigns, September 2026 is the month AI Max migration stopped being optional. Google began automatically upgrading Campaign-level Broad Match and standalone Automatically Created Assets (ACA) campaigns to AI Max between September 1 and September 30, 2026, according to Search Engine Land and Search Engine Roundtable — and once a campaign migrates, there is no way to revert it to the old settings. Microsoft Advertising has followed with its own AI Max, switched on by default for new Search campaigns. For marketing and growth teams anywhere in the world, this is one of the most consequential platform changes of the year, because it touches account structure, reporting, and creative control all at once.

This article walks through what is actually changing, the timeline Google has locked in, what the data says about how marketers are handling AI in paid media generally, and what to check in your own account before the migration reaches you. For more department context, see kurums.com’s Marketing department hub.

What exactly is migrating to AI Max, and when?

Google is automatically upgrading two legacy Search campaign configurations — Campaign-level Broad Match and standalone Automatically Created Assets — to AI Max between September 1 and 30, 2026, carrying over existing brand inclusions and exclusions in the process.

According to Search Engine Land’s reporting on Google’s migration timeline, the company already stopped allowing advertisers to create new Campaign-level Broad Match or legacy ACA campaigns on August 3, 2026, across the Google Ads UI, Ads Editor, and API. Campaigns using Automatically Created Assets will be upgraded to AI Max with search term matching and text customization enabled by default; campaigns using the campaign-level broad match setting will upgrade to AI Max with search term matching enabled by default. Google has said campaigns will be “migrated in place using equivalent AI Max settings to minimize disruption,” but “equivalent” does not mean “identical” — AI Max introduces broader matching and generative asset behavior that legacy settings did not have.

What happens to Dynamic Search Ads and older API integrations?

Dynamic Search Ads (DSAs) are on a separate, later timeline — migration for DSAs does not begin until February 2027, giving advertisers a longer runway to prepare, though Google will start sending in-account notices encouraging voluntary upgrades as early as September 2026.

Search Engine Land also reports that older Google Ads API versions supporting legacy Broad Match and ACA entities are scheduled to sunset in September 2027, a full year after the initial Search campaign migration. Development and marketing operations teams that built reporting, bidding automation, or QA tooling against the old entity structures have roughly a year to update those integrations before they stop working. That may sound like a long runway, but PPC Land’s coverage of the same rollout notes Google had already blocked new broad-match campaign creation a full month before the automatic migration began — a pattern suggesting the actual enforcement timeline tends to move faster than the headline dates imply.

Why is Google forcing this migration instead of leaving it optional?

Google frames AI Max as a performance upgrade that consolidates several manual Search features into one AI-managed system, and a mandatory migration is the fastest way to move its entire advertiser base onto that system without waiting for voluntary adoption.

This fits a broader pattern documented in Smartly’s 2026 Digital Advertising Trends Report: the report found that 46% of marketers already use AI to scale creative production, and 33% use AI across creative, media, and measurement simultaneously. Google and Microsoft are not creating demand for AI-managed campaigns from nothing — they are formalizing a shift that was already underway, and using a hard deadline to accelerate advertisers who had not yet moved voluntarily. The commercial logic is straightforward: AI Max campaigns generate more automated creative variations and broader keyword matching, which increases the surface area Google can serve ads against, benefiting Google’s own ad delivery efficiency as much as advertiser performance.

Is this migration actually good for advertiser performance?

It depends heavily on account hygiene going into the migration — accounts with clean negative keyword lists, accurate brand exclusions, and well-structured Automatically Created Assets tend to transition smoothly, while accounts with messy legacy settings risk broader, less controlled matching after the upgrade.

The Smartly report’s other findings are a useful gut check here. It found that 41% of marketers still need three to four weeks to go from asset creation to campaign launch, and only 3.6% can launch in under a week — meaning most advertising teams are not yet operating at the speed AI-managed campaigns are built for. The same report found marketers estimate roughly 20% of annual digital marketing spend is wasted, but that “Precision-First Marketers” who combine AI adoption with platform diversification are 27% more likely to keep waste under 10% of media budget. The takeaway is not that AI Max is inherently good or bad for performance — it is that the advertisers who benefit most are the ones who already have disciplined account structures and clear measurement, not the ones hoping automation will fix underlying account problems.

How should marketing teams prepare before their campaigns are migrated?

Audit search term reports, negative keyword coverage, and brand controls now, rather than after the automatic upgrade lands, since AI Max’s broader search-term matching means poor account hygiene becomes more visible — and more expensive — once it takes effect.

Three concrete steps are worth prioritizing in September 2026. First, review every campaign still on Campaign-level Broad Match or standalone ACA and confirm negative keywords are comprehensive, since AI Max will match more broadly against whatever search-term boundaries already exist. Second, document brand messaging guidelines clearly for any Automatically Created Assets, because generative text customization under AI Max pulls more heavily from account signals once enabled by default. Third, set a calendar reminder to review performance data seven and thirty days after migration specifically — Search Engine Land’s reporting suggests Google intends the transition to be low-disruption, but “low-disruption” for Google’s aggregate advertiser base does not guarantee a smooth transition for any individual account.

What does this mean for marketing budgets heading into 2027?

Expect Search budget allocation to become less granular and more outcome-based, as AI Max consolidates settings that used to let advertisers fine-tune match types and asset combinations manually, shifting the practical lever from campaign structure to bidding targets, budget caps, and creative input quality.

This mirrors the direction Smartly’s report describes across the industry: marketers increasingly want predictive tools to forecast performance before launch (31%), synthetic-audience testing before spend commits (40%), and AI validation of message fit (22%) — all signs that budget-setting is shifting earlier in the process, before creative goes live, rather than being adjusted campaign-by-campaign after the fact. Finance and marketing leaders planning 2027 budgets should treat Search campaign management as increasingly a function of input quality — creative assets, landing pages, conversion tracking — rather than manual bid and match-type tuning, because AI Max removes much of the latter as a lever entirely.

Frequently Asked Questions

When did Google’s AI Max migration for Search campaigns start?

Google began automatically migrating Campaign-level Broad Match and legacy Automatically Created Assets campaigns to AI Max on September 1, 2026, with the migration window running through the end of September 2026.

Can advertisers opt out of the AI Max migration?

No. Once a campaign is automatically migrated, there is no option to revert to the legacy Campaign-level Broad Match or standalone Automatically Created Assets configuration; Google also stopped allowing new campaigns to be created with those legacy settings starting August 3, 2026.

Does AI Max affect Dynamic Search Ads too?

Not yet. Dynamic Search Ads migration to AI Max is scheduled for February 2027, though Google began sending in-account notices about the upcoming change starting in September 2026.

Is Microsoft Advertising making a similar change?

Yes. Microsoft has rolled out its own AI Max feature and turned it on by default for new Search campaigns, following a similar direction toward AI-managed campaign settings across major search ad platforms.

How much digital ad spend do marketers believe is wasted?

Smartly’s 2026 Digital Advertising Trends Report found marketers estimate roughly 20% of annual digital marketing spend is wasted, though marketers who combine AI adoption with platform diversification report significantly lower waste rates.

What should I check in my account before AI Max migration reaches me?

Review and tighten negative keyword lists, confirm brand exclusion settings are accurate, and document current Automatically Created Assets messaging guidelines, since AI Max’s broader default matching makes existing account hygiene issues more consequential, not less.

Key takeaways for marketing leaders

The AI Max migration is not a minor UI update — it is Google and Microsoft formally retiring manual match-type and asset control for the majority of Search advertisers, on a fixed and mandatory timeline. Teams with clean account hygiene going into September 2026 are best positioned to benefit; teams relying on manual match-type tuning to compensate for weak negative keyword coverage will likely see that gap become more visible and more expensive. For related coverage, see kurums.com’s Marketing tools and software comparisons and the latest posts on the Marketing category page.

Sources: Search Engine Land (“Google sets AI Max migration timeline for Search campaigns”); Search Engine Roundtable coverage of Google’s September 1 AI Max migration; PPC Land reporting on Google blocking new broad-match settings ahead of the migration; Smartly’s 2026 Digital Advertising Trends Report. Last updated: September 2026.