Universal commerce protocol

Google's Universal Commerce Protocol (UCP), announced 11 January 2026, is an open-source standard co-developed with Shopify, Etsy, Wayfair, Target and Walmart and endorsed by more than 20 partners including Adyen, American Express, Best Buy, Mastercard, Stripe, Visa and Zalando. It covers checkout, discounts, fulfillment, identity linking and order management over REST, MCP, A2A and AP2; a business declares its capabilities in a JSON profile at /.well-known/ucp and remains merchant of record. On Google, UCP-powered checkout puts a Buy button on eligible listings in AI Mode and Gemini; it is in early access for select merchants with a Merchant Center account, and Google's help covers products eligible in the US, Canada and Australia. On 20 May 2026 Google announced a cross-retailer Universal Cart, rollout to Canada and Australia and later the UK, and UCP for hotel booking and food delivery.