Callout extensions (callout assets) are short, non-clickable text snippets — up to 25 characters each — that appear after your ad's descriptions to highlight benefits like "Free Shipping", "24/7 Support", or "No Setup Fees". They add proof points and screen space without changing your ad copy.
Callouts are the simplest Google Ads asset: pure benefit fragments, no links, no destinations to maintain. They render as a dot-separated line under your descriptions, and because they are assets, their expected impact contributes to Ad Rank like sitelinks do — free auction-score improvement for an hour of writing.
Specs and mechanics: up to 25 characters each, though Google's own best practice is shorter — punchy 12–18 character callouts read better in the dot-separated row. You need at least 2 to show; 4–6 eligible callouts is the practical target, and Google selects up to 10 per impression depending on format and device, in any order. No end punctuation, no exclamation marks per ad policy, sentence case or title case both fine — just be consistent.
The craft is choosing facts that remove purchase anxiety rather than restating your headline. Strong callouts are concrete and verifiable: "Free 30-Day Returns", "Family Owned Since 1987", "No Credit Card Required", "Licensed & Insured", "Same-Day Dispatch". Weak callouts are adjectives: "High Quality", "Best Service", "Trusted". A useful test — if a competitor could not honestly say it, it is a good callout; if anyone could say it, it is filler.
Use the hierarchy: account-level callouts for universals (support hours, guarantees), campaign-level for category-specific facts, ad-group level only when a specific product needs specific proof. Like all assets, callouts report performance in the Assets tab; prune anything Google rarely serves.
E-commerce ad callout set: "Free Shipping Over €50" (22) · "30-Day Returns" (14) · "Ships In 24 Hours" (17) · "4.8★ From 2,000+ Orders" (23). Each under 25 characters, each a concrete claim a hesitant buyer cares about.
Sitelinks are clickable links to specific pages with their own titles and descriptions; callouts are non-clickable text fragments. Sitelinks route users; callouts persuade them. Strong ads use both — they occupy different lines of the ad.
Google can show up to 10 per impression, but 2 is the minimum for eligibility and 4–6 well-written callouts is the practical sweet spot. Selection and order are automatic per auction.