Performance Max now takes 10,000 negative keywords, so use them with care
Google raised the Performance Max negative keyword cap from 100 to 10,000. Here is what that does and does not control, and how to avoid choking the campaign.
Google announced this week that Performance Max campaigns can now hold up to 10,000 negative keywords, up from 100, bringing the cap in line with Search campaigns. The rollout is expected to take a couple of weeks, so you may not see it in every account yet. For advertisers who have wanted tighter control over what Performance Max serves on, this is useful. It is also easy to misuse.
What the change covers
Three details from the announcement, as reported by PPC Land, set the boundaries:
- Negatives can be added at the campaign level or the account level.
- They apply to Search and Shopping inventory only. They do not affect YouTube, Display, or the other places Performance Max can serve.
- Negative keyword lists are not supported in Performance Max yet. Google said it plans to add support later in 2025. Treat that as planned, not available.
The last point matters operationally. Until lists arrive, a shared exclusion set means adding the same terms to each campaign by hand, or using account-level negatives, which apply across all Search and Shopping inventory, including your Search campaigns. Account-level is the blunter tool, so confirm that you want every campaign blocked before you use it.
Where negatives help
The most defensible uses are exclusions you would be comfortable defending to the person paying the bill:
- Irrelevant intent. Terms signaling jobs, free, DIY, repair, or a product category you do not sell.
- Brand protection from the wrong direction. If you run a separate brand Search campaign to control messaging and bidding, you may want Performance Max to stay away from brand queries. Test this carefully, since cutting brand traffic from Performance Max can lower its reported conversions while the brand campaign picks up the same customers.
- Known low-margin queries. For an ecommerce app or store, terms that match products you carry but sell at a loss.
Where they hurt
Google's own commentary, per PPC Land, was to use negatives judiciously and to remember how match types behave. That is the right instinct. A few failure modes to avoid:
- Over-blocking broad terms. A single-word negative on broad match can remove a large amount of valid traffic, since match behavior is looser than many people expect. Prefer phrase or exact match negatives unless you have a clear reason.
- Judging on short windows. A campaign that learns from conversion data will shift after you change its inventory. Make the change, then leave it alone for a full cycle of your conversion delay before you decide whether it worked.
- Changing many things at once. If you add 500 negatives, a new feed and a new target on the same day, you cannot attribute any result to any of them.
A sensible way to roll this out
Start with what you can already see. Pull the search terms you have visibility into and sort by spend. Mark terms that are plainly irrelevant, and queue those first. Add them in batches of a manageable size, keep a dated change log, and compare cost per conversion and conversion volume before and after, not just cost per conversion. A lower cost per conversion with half the volume is not a win if volume was the goal.
A hypothetical shows why. Suppose a campaign spends $10,000 a month and gets 200 conversions, a $50 cost per conversion. After new negatives it spends $6,000 for 150 conversions, which is $40 each. The cost per conversion improved by 20 percent, but you lost 50 conversions. Whether that is good depends on whether the budget is capped by efficiency or by demand, and whether you can spend the freed $4,000 at a similar $50 or better.
Keep a record you can audit
Negatives are easy to add and easy to forget. Keep a simple sheet with each term, the date added, the campaign, the reason, and the person who approved it. Six months from now someone will ask why a product line has no traffic, and the answer should take a minute to find. Review the list quarterly and remove terms that no longer apply, such as a discontinued product, a finished promotion, or a competitor name you decided to bid on after all.
Also check how negatives interact with the rest of your account. If you use account-level exclusions, a term added for one campaign's sake can silently block another that wants that traffic.
The practical takeaway: use the larger limit to remove clear waste, keep exclusions narrow, and hold off on building a shared list structure until Google ships lists.