Format and limits
Each impression shows at least one headline and one description, combined in varying order. Headline 1, Headline 2 and Description 1 always show; Headline 3 and Description 2 are not guaranteed. Required text, such as a legal disclosure, must be pinned to one of the three always-visible positions.
- Headlines: 3 minimum, 15 maximum, 30 characters each.
- Descriptions: 2 minimum, 4 maximum, 90 characters each.
- Display path: 2 fields of 15 characters, such as /plumbing/emergency.
- Pinning: a headline can be fixed to position 1, 2 or 3 and a description to position 1 or 2.
Writing headlines that combine well
Each headline must make sense on its own and next to any other. Vary the angle instead of rewording one sentence: main keyword, benefit, hard proof, offer, timing, call to action. Fifteen headlines that all say “cheap plumber” leave Google with no real choice.
Google recommends at least two responsive search ads per ad group, each rated Good or Excellent for Ad Strength and each with its own final URL. Ad Strength mostly grades variety and keyword use: it flags a thin ad, but it does not replace looking at conversions.
To pin or not to pin
Google advises most advertisers against pinning, because it cuts the number of possible combinations and can lower Ad Strength. Keep it for real constraints: a legal disclaimer, a mandated brand name, a regulated price claim. If you pin, place two or three different headlines in the same position so the system still has options, and never two nearly identical lines.