AI Max and Performance Max in 2026: Controls, Changes and Guardrails

In April 2026 Google announced that Dynamic Search Ads, automatically created assets and campaign-level broad match would all be folded into AI Max for Search campaigns, and that AI Max had left beta with hundreds of thousands of advertisers using it ¹. Automatic upgrades for automatically created assets and campaign-level broad match began in September 2026, while the Dynamic Search Ads sunset was pushed back to February 2027 ¹. Together with Performance Max, this means most Google Ads budgets now run through AI-led campaign types. The question for marketing leaders is not whether to use them but how to keep control.

What AI Max for Search does

AI Max is a set of features layered onto a standard Search campaign rather than a separate campaign type. Google launched it in May 2025 ². It has three main parts ¹:

• Search term matching. Uses broad match and "keywordless" technology to find relevant queries beyond your keyword list ².
• Text customisation. Generates headlines and descriptions from your site and existing ads.
• Final URL expansion. Sends users to the page on your site that Google judges most relevant, rather than the one you set.

Alongside these come controls that matter for governance: brand inclusions and exclusions at campaign and ad group level, ad group-level "locations of interest" targeting, URL inclusions and exclusions, and the ability to remove generated assets ². Reporting was also expanded, with the search terms report showing the headline and landing page served, and asset reports showing spend and conversions ².

What the performance data says

Google's own figures are positive. At launch it said advertisers turning on AI Max typically see 14% more conversions or conversion value at a similar CPA or ROAS, rising to 27% for campaigns that rely mainly on exact and phrase match ². In 2026 it added that campaigns already using search term matching saw an average 7% more conversions or value at similar efficiency after also enabling text customisation and final URL expansion ¹. Both figures come from Google's internal data for non-retail advertisers ¹².

Independent analysis is more mixed. Mike Ryan of Smarter Ecommerce analysed more than 250 campaigns and found a median 13% increase in revenue but a median 16% increase in CPA, with ROAS outcomes ranging from +42% to -35% ³. He described switching on AI Max as "essentially a coin toss" and flagged four pitfalls: cannibalisation of existing broad match traffic, what he called competitor hijacking, reporting overload, and wasted spend on the Search Partner Network, where one dataset showed a 0.07% conversion rate against 3.04% on Google Search ³.

The fair reading is that AI Max can find additional volume, but efficiency depends heavily on the account. Retail advertisers in particular should note that Google's headline uplift figures exclude retail ³.

What changed in Performance Max

Performance Max (PMax) runs one campaign across Search, YouTube, Display, Discover, Gmail, Maps and Search partners. For years the main complaint was opacity. A series of changes since 2025 has addressed much of that:

Change	When	What it gives you
Negative keyword limit raised from 100 to 10,000	March 2025	Real query control on Search and Shopping inventory 4
Campaign-level negative keyword lists	Rolled out in 2025	Reusable exclusions across campaigns 5
Channel performance report	Announced April 2025	Clicks, conversions, spend and conversion value by channel, plus diagnostics 6
Full search terms report	Completed in 2025	The queries behind Search performance, with a source column 5
Demographic exclusions and device targeting	Generally available in 2025	Exclude age groups; target computers, mobiles or tablets 5
Channel data in the Google Ads API (v23)	February 2026	Channel breakdowns at campaign, asset group and asset level, for dates from 1 June 2025 7

When the channel report was announced in April 2025, Google confirmed that channel exclusions were still not available in PMax ⁶. That remained the biggest gap through most of 2026.

Update, 15 October 2026: Google has since announced channel prioritisation and budget allocation controls. In PMax, advertisers can mark search partners and the Google Display Network as low priority and cap their daily share of budget, including setting it to 0%; Google's own surfaces such as YouTube and Gmail stay grouped as "Google channels" and cannot be ranked separately ⁸. The controls are rolling out progressively from 15 October 2026, initially in the Google Ads interface and Search Ads 360, with API support to follow ⁸.

When to use which

There is no universal answer, but some patterns hold:

1. Use AI Max inside existing Search campaigns when you have solid conversion tracking, a well-structured site and room to grow beyond your keyword list. Test it as an experiment against the same campaign without AI Max ¹.
2. Keep exact and phrase match campaigns for core and brand terms where you need predictable cost and message control.
3. Use PMax for ecommerce with a strong product feed, or for lead generation where you can feed back qualified lead or revenue data, and where the full Google inventory suits the funnel.
4. Be careful running PMax and AI Max on the same queries. Overlap makes it hard to see which campaign is doing the work, and cannibalisation is one of the pitfalls independent analysis has identified ³.

Guardrails to set

AI-led campaigns perform best when the inputs are good and the limits are clear. A practical checklist:

• Conversion data first. Import offline or CRM conversions and use value rules so the algorithm optimises for revenue or qualified leads, not cheap form fills.
• Brand exclusions and inclusions. Stop AI Max and PMax claiming brand traffic that a cheaper brand campaign would win, and decide whether competitor terms are allowed ².
• URL exclusions. Keep traffic away from careers, support, blog or legal pages that rarely convert ².
• Negative keyword lists. Apply shared negatives across Search and PMax, now that the limits allow it ⁴⁵.
• Review generated text. Check text customisation output for brand voice and regulatory accuracy, and remove assets that do not fit ².
• Watch Search partners. Review channel reports monthly and use the new low-priority setting where partner traffic does not convert ³⁸.
• Run experiments. Use Google's experiment tools rather than switching features on account-wide, and judge results over several weeks.

Key takeaways

• Dynamic Search Ads, automatically created assets and campaign-level broad match are being folded into AI Max, with automatic upgrades from September 2026 and the DSA sunset in February 2027 ¹.
• Google reports 7-27% more conversions from AI Max in its internal data, but independent analysis found higher revenue alongside higher CPA ¹²³.
• PMax now offers channel reporting, search terms, 10,000 negatives and demographic and device controls ⁴⁵⁶.
• New channel prioritisation controls let advertisers cap search partner and Display spend in PMax from October 2026 ⁸.
• Strong conversion data and clear exclusions matter more than campaign type.

What this means for your brand

Check which of your Search campaigns were auto-upgraded in September and review their search terms, landing pages and generated text now. Set brand, URL and negative keyword controls before you scale spend, not after. Measure AI Max and PMax against business outcomes from your CRM or data warehouse rather than in-platform conversions alone. We would test channel prioritisation as soon as it reaches your account, starting with search partners.

Sources

1. We're upgrading Dynamic Search Ads to AI Max - Google, April 2026 (updated June 2026)
2. Unlock next-level performance with AI Max for Search campaigns - Google, May 2025
3. AI Max increases revenue 13% but drives higher CPA: Study - Search Engine Land, March 2026
4. Google raises negative keywords limit to 10,000 for Performance Max campaigns - PPC Land, March 2025
5. Google wraps up Performance Max feature rollouts in 2025 - PPC Land, August 2025
6. Channel Reporting Is Coming To Performance Max Campaigns - Search Engine Journal, April 2025
7. Google Ads API update cracks open Performance Max by channel - Search Engine Land, February 2026
8. Google Ads lets advertisers limit Display and partner spend by percentage - PPC Land, October 2026

Figures and product details are as reported by the sources listed, at the time of writing. Platforms change quickly, so check the latest documentation before acting on any single number.