A product page qualifies for Google's merchant listings only if its Product markup includes a name, an image and an Offer with a price greater than zero plus a currency. Availability, shipping, returns and reviews are optional but strongly recommended. This guide is the practical version for a small online shop.
I explain the difference between merchant listings (pages where you can buy) and product snippets (pages that discuss products), then the rules that trip small shops: one product per page, one currency per URL, markup that matches the visible page, and Product markup in the server-rendered HTML rather than injected by JavaScript. There's a complete example and the advice to generate it from the same database row that renders the visible price, so the two can never disagree.
Shipping and returns are now best described once for the whole store under Organization, with per-product overrides for exceptions like bulky items or final-sale goods, and I explain Google's precedence order when sources disagree. I also cover variants with ProductGroup and which reviews a shop may mark up: genuine reviews of a specific product, never star ratings for the business itself.
Finally, how structured data and a Merchant Center feed work together for free listings and Google's AI shopping features, what OpenAI says about ChatGPT product results, and the common mistakes to test for.
Key takeaways
- Product needs name, image and an Offer with price and currency
- Generate markup from the same data as the visible price
- Describe shipping and returns once at store level
- Mark up product reviews, not business star ratings
- Pair structured data with a Merchant Center feed
Related on BuiltToWinWeb: how AI agents will buy from shops
Read the full guide on BuiltToWinWeb: The product schema guide for small shops
A summary by Jacob Campbell of an article first published on built2winweb.com on October 7, 2026.