Ad extensions and assets: sitelinks, callouts, and structured snippets
An ad from part 6 is headlines and descriptions alone — extensions (Google now calls them "assets," the same feature under a renamed label) add extra, structured information beneath the main ad: links to specific pages, short callouts, a phone number. They cost nothing extra to add and directly help both click-through rate and Quality Score.
Sitelinks: extra links to specific pages
Sitelink 1: Gift Subscriptions → /gift
Sitelink 2: Subscription Plans → /plans
Sitelink 3: About Our Roasting → /about
Sitelink 4: Customer Reviews → /reviewsSitelinks give a searcher more than one specific destination to choose from, directly in the ad — someone specifically interested in gifting skips straight to /gift instead of landing on a general homepage and having to navigate from there themselves. Each sitelink can (and should) have its own short description text too, giving Google more relevant, specific content to match against a given search.
Callout assets: short, punchy specifics
Free Shipping · Cancel Anytime · 48-Hour Roast-to-Ship · Loved by 10,000+ SubscribersCallouts are short (25-character) phrases with no link of their own — pure additional information appended to the ad. They're the right place for exactly the kind of specific, concrete detail from part 6's ad copy discussion: a real number, a real policy, a real guarantee, rather than vague reassurance.
Structured snippets: a specific, labeled category
Types: Light Roast, Medium Roast, Dark Roast, DecafStructured snippets use a predefined header ("Types," "Brands," "Styles," among others Google offers) followed by a comma-separated list — a compact way to communicate real product variety directly in the ad, without needing a full sentence of description space to do it.
Call and location assets, when they're real
Call: (555) 010-2938
Location: 412 Roaster's Row, Portland, ORA call asset only makes sense for a business that genuinely wants and can handle phone inquiries directly from an ad — for Bright Leaf Coffee's e-commerce subscription model, this isn't relevant; for a local coffee shop, or for GreenDesk's B2B sales process (part 17), a call asset can be a meaningfully higher-intent conversion path than a web form.
Why extensions genuinely affect Quality Score, not just visible size
Google's own Quality Score system (part 9) factors in the expected click-through rate of an ad, and extensions measurably increase it — more visible information and more specific links directly correlate with more clicks in Google's own data. This means extensions aren't purely a cosmetic addition; they're a real, if secondary, lever on the exact same Ad Rank formula from part 1.
Which extensions actually apply
Not every extension type fits every business — Bright Leaf Coffee benefits from sitelinks, callouts, and structured snippets, while a call extension adds little value for a self-serve subscription checkout flow. Adding an extension type that doesn't genuinely serve the business, purely because it's available, dilutes the ad's real estate without adding real value to a searcher deciding whether to click.
Setting up extensions once at campaign launch and never revisiting them. Sitelinks pointing at a page that's since changed, or a callout advertising a promotion that's ended, actively misleads a searcher into clicking expecting something that's no longer true — extensions need the same ongoing maintenance as the core ad copy itself.
Next: the page an ad actually sends traffic to — a click is worthless if the landing page doesn't convert it into a subscriber or a lead.