OpenAI retires ChatGPT Ads' bid caps for average cost targets

OpenAI has begun retiring the two bid caps that have governed ChatGPT Ads since the product launched, replacing Max Bid and Max CPC with average cost targets that let its system pay more than your number in one auction and less in the next, as long as the campaign average lands near the goal you set.

OpenAI told advertisers about the change by email, and the shift began rolling out on Monday, November 9. Search Engine Journal and Search Engine Roundtable both reported the same timeline independently, citing OpenAI's own documentation and advertiser emails, which puts this past the single-source threshold that usually keeps a platform-bidding tweak out of this column.

A ceiling becomes an average

Max Bid and Max CPC did what their names say: they capped what OpenAI's system could pay in any individual auction for a conversion or a click. Target CPA and Target CPC, the two new options, work differently. They're averages, not ceilings. The system can bid well above your target on an auction it thinks is worth it, and well below on one it isn't, so long as the campaign settles near your chosen number over time.

Search Engine Journal's illustration makes the arithmetic concrete: a campaign that spends $400 and lands 10 purchases has an actual cost per acquisition of $40, whether or not any single purchase actually cost $40. Set a $20 target and you are not buying purchases at $20 each — you're asking the system to aim its average there, which it may or may not hit depending on how much signal it has to work with.

The rollout is staged. From November 9, every new conversion campaign in ChatGPT Ads Manager defaults to Target CPA instead of Max Bid, and new click campaigns can choose Target CPC instead of Max CPC. Existing campaigns keep running under their old caps until an advertiser switches them, or until January 1, 2027, when OpenAI moves whatever is left over automatically. According to Search Engine Journal, OpenAI's own documentation does not say what target value that automatic migration will assign — which means the advertisers who wait get a number chosen for them instead of one they picked.

OpenAI is also renaming its autobid option, previously "Maximize results," to "Intelligent bidding." Manual Max Bid survives as an option for anyone who still wants a hard ceiling, and Search Engine Journal reports that OpenAI's help documentation continues to recommend starting a CPC campaign with a $3 to $5 maximum bid as a baseline — a figure worth knowing even if you move straight to a target.

Who this actually hits

ChatGPT Ads is still a rounding error next to Google and Meta in most software marketing budgets, but a growing number of SaaS and B2B teams have started testing it as a top-of-funnel channel, betting that OpenAI's audience skews toward people already shopping for a solution. For anyone running conversion or click campaigns there, this is not a cosmetic UI change — it's a change in what "winning" the auction costs you, and how predictable that cost is week to week.

The sharper risk sits with agencies and any marketer managing ChatGPT Ads through an API or a third-party tool rather than the Ads Manager UI directly. Search Engine Journal reports that starting November 18, a Max Bid or Max CPC value sent through legacy API fields will be read as an average target rather than a ceiling the moment a campaign is created or an ad group's bid type changes — even though the legacy fields themselves keep functioning through December. A number an agency set as a hard spending guardrail could quietly become a performance goal instead, with no error message to flag the change.

OpenAI told advertisers they "can optionally choose a cost target in Ads Manager" starting November 9, before the switch becomes automatic for everyone else in January.

What to do before January

The advertisers OpenAI is implicitly rewarding here are the ones who set their own target deliberately instead of waiting for the January migration to pick one for them.

• Pull your actual recent CPA or CPC from campaign history before setting a target — OpenAI's own guidance, per Search Engine Journal, warns that an aspirational number set below real performance can throttle delivery and leave budget unspent.
• Check that your Pixel or Conversions API is sending the event you're optimizing toward, and watch for Event Quality Score warnings, which flag the signal problems that make a target unreliable.
• If an agency or a connected tool manages your bids through the API, confirm with them what happens to any Max Bid value after November 18 — it may already be acting as an average rather than a cap.
• Decide before January 1, 2027. Switching on your own terms means choosing the number; waiting means accepting whatever OpenAI assigns.