Search themes are optional signals you add to a Performance Max asset group to tell Google which searches matter to your business. You can add up to 50 per asset group. They expand reach rather than limit it, and they compete like phrase or broad keywords. Control comes from pairing them with negatives, brand exclusions and the search terms report.
- Google allows up to 50 search themes per asset group, each up to 80 characters.
- Search themes add reach. They do not restrict Performance Max to those searches.
- An exact match keyword in a Search campaign that is identical to the query still wins over Performance Max.
- Real control comes from campaign negatives (up to 10,000 per campaign), brand exclusions and the search terms report.
What are search themes in Performance Max?
Performance Max does not use keywords. It reads your landing pages, your assets and your conversion data, then decides which searches to show up for. Search themes are a way to add your own input to that process. You type in topics your customers search for, and Google uses them as extra signals.
Google describes them as most useful when its AI cannot quickly learn something about your business on its own. Think of a new service line, a new city, a seasonal promotion, or pages that do not explain your offer well. In early 2024, Google also folded custom intent segments into search themes, so this is now the main place to give Performance Max search intent.
The limit started at 10, rose to 25 in late 2023, and moved to 50 in a staged rollout from May 2025. If your account still shows 25, check again later. The interface tells you the cap when you add themes.
Do search themes limit where my ads show?
No. This is the most common misunderstanding. Search themes do not narrow your traffic. Performance Max keeps matching searches it finds through your URLs and assets, and themes add more on top. Google says they can help find incremental traffic that Final URL expansion would miss.
So if you add "emergency plumber Dallas" as a theme, you are not telling Google to show ads only for that. You are saying: this matters, go find more of it. If you want Performance Max to stay away from certain searches, you need negatives and exclusions, covered below.
Search themes vs keywords: who wins the auction?
Most small businesses run Performance Max next to a Search campaign. Both can be eligible for the same search, so you need to know which one Google picks. Google uses a simple order of preference.
| Situation | Who gets priority |
|---|---|
| Exact match keyword in a Search campaign that is identical to the query | The Search campaign, every time it is eligible to serve |
| Phrase or broad keyword vs a Performance Max search theme identical to the query | They share priority. The higher Ad Rank wins |
| Performance Max with no matching search theme | Treated like a keyword that does not exactly match the query |
| Shopping ads | Not covered by these rules. They can show next to a Search ad |
"Identical" includes spell-corrected searches but not plurals or synonyms. A keyword also has to be eligible to serve. If your Search campaign is capped by budget or the ad is disapproved, the search can go to Performance Max instead.
The practical takeaway: your highest-value searches belong in a Search campaign as exact match keywords. That is where you get full control over the ad, the bid and the landing page. Use search themes to cover the wider set of intents you do not want to manage one keyword at a time.
How to choose good search themes
Good themes describe what a buyer types when they are close to acting. They are not a list of every word related to your industry. Use this process.
- 1Pull your top converting search terms from any Search campaign, from Search Console queries and from what customers say on the phone.
- 2Group them by intent: the service, the problem, the location, and urgency words like "same day" or "near me".
- 3Write one theme per distinct intent. Skip near-duplicates. Google’s own example: do not add both "car" and "automobile", since they reach the same people.
- 4Match each asset group’s themes to its landing page and assets. A roofing asset group should not carry gutter cleaning themes.
- 5Add themes for new offers or markets where Google has little data yet. This is where they help most.
- 6Leave room. You do not have to use all 50. Ten sharp themes beat fifty vague ones.
Can I use competitor names as search themes?
Google allows competitor brand and product names as themes, as long as you follow its policies and the law. Whether it is smart is another question. Competitor traffic is often expensive and converts poorly for local service businesses. Test it in its own asset group so you can measure it apart.
How do I stop Performance Max from showing on the wrong searches?
Search themes push. Negatives and exclusions pull. You need both to control intent.
| Control | What it does | Where it applies |
|---|---|---|
| Campaign negative keywords | Blocks searches containing those terms | Search and Shopping inventory only |
| Account-level negative keywords | Blocks terms across all eligible campaigns | Search and Shopping, including Performance Max |
| Shared negative keyword lists | One list reused across campaigns | Campaigns you attach it to |
| Brand exclusions | Keeps your own or other brand searches out | Search and Shopping; themes respect them |
Note the limit: negatives do not apply to YouTube, Display, Gmail or Discover placements. They only shape which searches you pay for.
A starter negative list for service businesses
- Job seekers: jobs, hiring, salary, careers, apprenticeship.
- Do-it-yourself intent: how to, DIY, tutorial, video, parts.
- Free and cheap intent, if it does not fit your offer: free, cheap, coupon.
- Services you do not offer, and cities you do not serve.
- Your own brand, if a separate brand Search campaign already covers it. Use brand exclusions for this.
How to see which searches Performance Max is buying
For years, the biggest complaint about Performance Max was that it hid search terms. That changed. On April 30, 2025, Google announced full search terms reporting for Performance Max, with the same query detail Search and Shopping campaigns get, plus a channel performance report that breaks results out by Search, YouTube, Display and other channels.
- 1Open the campaign and go to Insights and reports, then Search terms.
- 2Sort by cost. Look at the top 50 terms first.
- 3Mark terms that bring leads you want. Consider adding the best ones as exact match keywords in your Search campaign.
- 4Add irrelevant terms as negatives at the campaign or account level.
- 5Check the channel performance report to see how much spend goes to Search vs other channels.
- 6Repeat weekly for the first month, then every two weeks.
How to measure if search themes are working
Google suggests comparing campaign-level performance before and after adding themes, and using search term insights to see the new searches you reached. Keep it simple.
- Note your cost per lead and lead volume for the 30 days before the change.
- Add themes to one asset group at a time, so you know which change did what.
- Wait at least two to three weeks before judging. Automated bidding needs time to adjust.
- Judge on qualified leads from your CRM, not form fills alone. A theme that brings cheap junk leads is not working.
When search themes are not the answer
If you have a small budget and a few high-value services, a well-built Search campaign with exact and phrase match keywords usually gives you more control than Performance Max. Performance Max works best when you have steady conversion volume, good creative for several channels and clean conversion data. Search themes help steer it. They do not turn it into a Search campaign.
Frequently asked questions
Up to 50 per asset group, each up to 80 characters. Some accounts saw the old cap of 25 during the 2025 rollout.
Not quite. Google treats them like phrase or broad match keywords for priority, but they add reach rather than limit it. Performance Max still matches other searches based on your URLs and assets.
Not for queries identical to your exact match keywords, as long as the Search campaign is eligible to serve. For phrase and broad matches, the higher Ad Rank wins.
Yes. You can add up to 10,000 negative keywords per campaign, plus account-level negatives and shared lists. They apply to Search and Shopping inventory only.
They are optional. They help most when you launch a new service, enter a new market or run a promotion Google has no data on yet.
- Google Ads Help, About search themes in Performance Max campaigns
- Google Ads Help, Unlock new relevant traffic on Performance Max with search themes
- Google Ads Help, Negative keywords in Performance Max campaigns
- Google Ads Help, More goals and controls coming to Performance Max (April 2025)
- Google Ads & Commerce Blog, Channel performance reporting coming to Performance Max
- PPC Land, Google doubles search themes limit (May 2025)
