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How to write Google responsive search ad headlines and descriptions

A Google responsive search ad lets you supply up to 15 headlines (30 characters each) and up to 4 descriptions (90 characters each), and Google assembles combinations to test. Write headlines that mirror what people search, state your offer and proof, and make sure any headline can sit next to any other without contradicting it.

By the Moonlighters team. Last updated 12 October 2026.

How responsive search ads work

Instead of one fixed ad, you give Google a pool of headlines and descriptions. It tries combinations and learns which work for different searches. You can supply as many as 15 headlines and 4 descriptions, with a minimum of 3 headlines and 2 descriptions.

The limits

HeadlinesUp to 15, each up to 30 characters
DescriptionsUp to 4, each up to 90 characters
Display pathTwo short optional fields added to the displayed web address

Limits can change. Check Google's current documentation before you write at length.

What to put in the headlines

  • Match the search. Include the service and the place people type, such as "Mobile Car Valet Christchurch".
  • The offer. "Free Quote in 24 Hours", only if you can deliver it.
  • Proof. Years in business, a real rating, a licence or guarantee you stand behind.
  • Action. "Book Online Today", "Call Now".
  • Difference. What you do that others do not, if it is true.

What to put in the descriptions

  • One sentence on the benefit and who it is for.
  • One on proof or what is included.
  • One on the next step, with a deadline only if it is real.

Rules for writing the pool

  1. Every headline must stand alone. Google can put any headline in any position next to any other.
  2. Vary the angles. Fifteen versions of the same phrase give Google nothing to test.
  3. Use pinning sparingly. Pinning fixes a headline to a position, which reduces testing. Use it only for something that must always show, such as a legal line.
  4. Do not repeat the same words everywhere. Variety lets more combinations show.
  5. Keep claims true. Prices, guarantees and "best" claims need to be accurate and supportable.

Check and improve

  • Use the asset report in Google Ads to see which headlines get shown and which perform.
  • Review the search terms report and add headlines that echo the real searches that bring customers.
  • Make sure the landing page continues the promise. See the landing page checklist.

The Google Ads audit checklist shows where this fits in a wider review.

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