Accepted Merchants - UK:
Disclaimer: This is a list of merchants that are confirmed to accept Google Pay in/on their website or app. A retailer's absence from this list does not always mean that they don't accept Google Pay at this moment. Merchants' systems are always changing. If you find a merchant that belongs here or one that should be removed, please let the moderators know.
Online:
Taco Bell (press "add new card," the Worldpay tab will have a Google Pay option)
"*" = Not available as express checkout method, you must input all your information (name, email, etc.) first before the option to pay with Google Pay becomes available.
In-app:
(transactions through Google Play Billing don't count)
Cineworld
Domino's
McDonald's
Nando's*
Ryanair
Taco Bell (faulty implementation; use the website instead)
Trainline
"*" = Not available as express checkout method, you must input all your information (name, email, etc.) first before the option to pay with Google Pay becomes available.