What is the most reliable way to verify a customer's age?

The most reliable way to verify age is to check a valid, government-issued photo ID — such as a driver's license, state ID card, military ID, or passport — that shows the customer's date of birth and photo. Relying on appearance or simply asking the customer's age is not sufficient and is not a defense if the person turns out to be underage. Carefully examining a valid ID is the standard responsible-service practice and the seller's best protection against an illegal sale to a minor.