Responsive Search Ads (RSAs): Best Practices Guide

RSAs are the standard (and only) search ad format in Google Ads. You provide multiple headlines and descriptions, and Google's machine learning tests different combinations to find the best-performing mix for each auction.

Each RSA allows up to 15 headlines (30 characters each) and 4 descriptions (90 characters each). Google shows 2-3 headlines and 1-2 descriptions at a time, assembling combinations based on the user's search query, device, location, and other signals.

Google requires a minimum of 3 headlines and 2 descriptions. However, providing the minimum severely limits testing. Google's recommendation is 10-15 headlines and 3-4 descriptions. The more unique assets you provide, the more combinations Google can test, and the better your results over time.

### Headlines — The Diversity Principle

Your 10-15 headlines should cover as many different angles as possible. Aim for at least one headline in each of these categories: primary keyword (e.g., "Emergency Plumber Dubai"), secondary keyword variation (e.g., "24/7 Plumbing Service"), key benefit (e.g., "Arrive Within 30 Minutes"), pricing or offer (e.g., "Free Estimate — No Obligation"), social proof (e.g., "500+ Five-Star Reviews"), urgency or scarcity (e.g., "Limited Slots — Book Now"), call to action (e.g., "Call Now for Fast Service"), trust signal (e.g., "Licensed & Insured Plumbers"), location (e.g., "Serving All of Dubai"), and differentiator (e.g., "Same-Day Repairs Guaranteed").

Descriptions — The Detail Layer

Descriptions have more room (90 characters) so use them to elaborate on headline promises, include specific details (service hours, coverage area, process), reinforce your CTA, and mention secondary selling points.

After your RSA has accumulated enough impressions (typically 2-4 weeks), check asset performance. Go to Ads, click on the RSA, and select "View asset details." Each headline and description is rated as "Best" (strong performer), "Good" (solid contributor), "Low" (underperforming), or "Learning" (not enough data yet).

Replace "Low" rated assets with new variations. Keep "Best" and "Good" rated assets. Give "Learning" assets more time before judging.

Pinning locks a headline to a specific position (1, 2, or 3). Each position can have multiple pinned headlines — Google will rotate among them.

Use pinning when your brand name must always appear in Position 1, when a legal disclaimer or required text must always show, or when a specific offer must be front and centre. Avoid pinning every position — this turns your RSA into a static ad and eliminates Google's ability to test.

If you must pin, pin 2-3 headlines to the same position so Google still has some testing flexibility within that position.

Google rates your RSA's Ad Strength from "Poor" to "Excellent" based on the number of headlines and descriptions (more is better), uniqueness of headlines (different messaging, not variations of the same), keyword inclusion, and relevance diversity.

Aim for "Good" or "Excellent" but prioritise quality over score. Do not add filler headlines just to boost Ad Strength. A concise, well-written "Good" RSA often outperforms a padded "Excellent" one with diluted messaging.

Writing 15 headlines that all say the same thing differently (wastes testing capacity), pinning all three positions (eliminates testing), ignoring asset performance reports (missing easy optimisation), using very short descriptions that waste the 90-character limit, and not including any keyword in headlines (hurts ad relevance).