AI Max auto-upgrade: what to check when CPA rises
Summary
Google’s automatic upgrade ran from September 1 to 30 and moved campaign-level broad match and Automatically Created Assets campaigns onto AI Max with only some of its features switched on. A September CPA increase isn’t proof that the upgrade caused it, though independent analysis found a median CPA increase of 16% among advertisers who chose AI Max. Timing, conversion delay and controls are worth checking before deciding to keep, fix or turn it off, because switching it off also disables the brand exclusions the migration carried over.
Why the migration matters for CPA
Cost per acquisition is the number most mid-market budgets are judged on, and the September migration changed settings in accounts without a decision from the advertiser. Misreading that change has a cost either way.
Blaming the upgrade for a CPA increase that came from conversion delay or seasonality can lead to switching off features that were working, and the switch itself removes brand protection. Ignoring a real problem can let search terms drift into areas the business never intended to pay for.
Dynamic Search Ads face the same forced change in February 2027, so the work done on September’s data sets up that migration.
In August, we covered the dates in “Google Locks In September and February Deadlines for AI Max Migration.” Google blocked new campaign-level broad match and legacy Automatically Created Assets setups on August 3, then ran the automatic migration from September 1 to 30.
With those dates behind us, the question is what the move did to cost per acquisition.
What the AI Max auto-upgrade changed in campaigns
Google migrated campaigns in place using equivalent settings. Existing brand inclusions and exclusions were preserved.
Campaigns using campaign-level broad match came out with search term matching on, and text customization and Final URL expansion off. Campaigns using standalone Automatically Created Assets came out with search term matching and text customization on, and Final URL expansion off.
The rollout was progressive, so change dates differ by campaign. Google scheduled it to run through September 30. Any campaign still showing legacy broad match or Automatically Created Assets settings is worth checking.
Dynamic Search Ads weren’t part of it. Their automatic migration runs in February 2027.
Why a higher CPA isn’t proof
Google’s benchmark is 14% more conversions or conversion value at a similar CPA or ROAS for advertisers who activate AI Max. It comes from 2025 internal data and covers non-retail advertisers who chose to turn it on. That number wasn’t built for campaigns moved without a decision, and none of the migrated campaigns came out with all three features on.
Independent analysis points the other way on efficiency. In March 2026, Smarter Ecommerce looked at more than 250 Search campaigns running AI Max and found a median conversion value lift of 13% alongside a median CPA increase of 16%. ROAS ranged from 42% above baseline to 35% below, and only 22% of campaigns landed near their original ROAS targets.
Two caveats: the analysis came from an ecommerce-focused firm, and it covered advertisers who chose the feature before the forced migration.
The same analysis flagged one account where it expanded so heavily into competitor brand terms that it took 69% of total Search impressions. It’s a single account, but it marks the extreme end of search terms drifting off target.
How to tell if the upgrade caused the increase
Timing
Compare the date CPA moved with the date each campaign migrated. Google’s developer documentation names API fields that record the migration date for every campaign. Without API access, change history can serve as a substitute.
Conversion delay
Google advises waiting at least one conversion cycle before judging performance, then checking again after one or two cycles so conversions are complete. In longer B2B sales cycles, late-September clicks may look worse today than they will once conversions are reported.
Other drivers
Google lists new keywords, ad copy and landing page changes as internal causes of performance swings, and seasonality and competition as external ones.
Settings visibility
Google is rolling out new reporting columns for locations of interest, optimized targeting and brand inclusions. They may not appear in every account yet, but they make it easier to audit which controls are active and compare campaigns.
Google’s AI Max auto-upgrade experiments compare a control with the feature off against a trial with it on, inside one campaign. The flow isn’t available for campaigns with text customization on, a portfolio bidding strategy, shared budgets, bidding exploration or another active experiment. Campaigns that came out of the Automatically Created Assets upgrade have text customization on, which rules them out. Google’s guidance for blocked campaigns is to build a new campaign without the legacy features and test there.
Keep, fix or turn it off
The decision works best campaign by campaign.
Keep it where CPA and lead quality hold once conversion delay is accounted for.
Fix it where search terms are drifting off target. Google confirms negative keywords are respected while it’s on. Brand exclusions, campaign-level URL exclusions and ad group level search term matching toggles give further control. Text customization can also be switched off on its own.
Turn it off where the evidence shows it isn’t earning its place.
Search term matching doesn’t work with manual CPC. AI Max relies on signals from automated bidding such as Maximize Conversions or Maximize Conversion Value.
What happens when AI Max is turned off
Google’s documentation says turning AI Max off disables all of its features, and brand exclusions stop working. Turning it back on restores the settings as they were originally set.
Brand controls carried over in the migration, so a campaign relying on them loses that protection the moment the toggle flips. Anyone planning to switch it off should record which controls are in use first and rebuild the equivalent protections.
Pinned assets need a quick check. Google says pinning isn’t respected when text customization and Final URL expansion are both on, or when URL inclusions are used. Upgraded campaigns came out with Final URL expansion off, so pins should still apply unless someone has since switched it on or added URL inclusions. Accounts that pin compliance language should confirm both settings.
Scripts and integrations are on a separate timeline. Future Google Ads API versions drop the legacy broad match and Automatically Created Assets entities. Older versions that still support them are expected to sunset around September 2027.
How to reset a CPA target after the migration
Google says CPA targets can change as often and by as much as an advertiser likes. Smart Bidding reacts immediately, doesn’t enter a learning status, and doesn’t reset what it has learned.
A large change can still bring volatility for a conversion cycle or two, because it moves the campaign into a different set of auctions. Google advises judging the result after one to two conversion cycles.
For a starting point, Google suggests historical CPA over a window that excludes the most recent days still waiting on conversions. With a two-day delay, that means a 28-day window excluding the last two days. Google also warns that overly aggressive targets reduce volume, and its simulators can help fine-tune the number.
In practice, that points to anchoring the target to a stable window and to what the business can afford, not to the worst weeks of September.
Dynamic Search Ads migrate next, in February 2027
Google began in-account notices in September, sends reminders on January 15, 2027, and migrates remaining campaigns between February 1 and 28 into standard Search with AI Max enabled. New DSA ad groups are permanently removed in that same window.
Advertisers who document what September did to their accounts will have a baseline to compare against when DSA campaigns convert in February.
For those who’ve already pulled the numbers, what moved first: cost, volume or lead quality?
Frequently asked questions
Did Google automatically upgrade my campaigns to AI Max?
Only some of them. From September 1 to 30, 2026, Google moved campaigns using campaign-level broad match and standalone Automatically Created Assets onto AI Max. Dynamic Search Ads migrate separately, between February 1 and 28, 2027.
What AI Max settings did the upgrade turn on?
Campaign-level broad match campaigns came out with search term matching on, and text customization and Final URL expansion off. Automatically Created Assets campaigns came out with search term matching and text customization on, and Final URL expansion off. Existing brand inclusions and exclusions were preserved.
Will AI Max raise my CPA?
Not necessarily, and the evidence is mixed. Google’s benchmark is 14% more conversions or conversion value at a similar CPA or ROAS, but that covers non-retail advertisers who chose to turn it on. Smarter Ecommerce found a median CPA increase of 16% alongside a 13% median conversion value lift across 250+ campaigns. Check conversion delay and migration timing before blaming the upgrade.
Can I turn AI Max off?
Yes, but it’s all or nothing. Google says turning AI Max off disables all of its features and stops brand exclusions from working. Turning it back on restores the original settings. Note which controls you rely on first.
Can I still use negative keywords and brand exclusions?
Google confirms negative keywords are respected while AI Max is on. Brand inclusions and exclusions carried over in the migration, and they stop working if AI Max is switched off.
Does AI Max work with manual CPC bidding?
No. Search term matching doesn’t work with manual CPC. AI Max relies on signals from automated bidding such as Maximize Conversions or Maximize Conversion Value.
How long should I wait before judging results?
Google advises at least one conversion cycle, then another check after one or two cycles so conversions are complete. In longer B2B sales cycles, late-September clicks may look worse now than they will once conversions are reported.
Can I A/B test AI Max on a campaign that was upgraded?
Often not. Google’s AI Max experiments aren’t available for campaigns with text customization on, portfolio bidding, shared budgets, bidding exploration or another active experiment. Upgraded Automatically Created Assets campaigns have text customization on, which rules them out. Google’s guidance is to build a new campaign without the legacy features and test there.
What happens to Dynamic Search Ads?
Google sends reminders on January 15, 2027, then migrates remaining campaigns into standard Search with AI Max enabled between February 1 and 28. New DSA ad groups are removed in that window.
Sources
Google Ads Developer Blog, Migrate Campaign-level Broad Match and Automatically Created Assets to AI Max, August 12, 2026
Search Engine Land, Google Ads adds new AI Max columns for deeper campaign analysis, October 7, 2026
Search Engine Land, AI Max increases revenue 13% but drives higher CPA: Study, March 5, 2026
Search Engine Journal, What SMEC’s Data Reveals About AI Max Performance, March 5, 2026
Google Ads Help, Optimize Google Ads with AI Max for Search campaigns, accessed October 9, 2026
Google Ads Help, Frequently asked questions about AI Max for Search campaigns, accessed October 9, 2026
Google Ads Help, About AI Max experiments, accessed October 9, 2026
Google Ads Help, How our bidding algorithms learn, accessed October 9, 2026
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