 Probably okay isn't okay, especially when it comes to drinking and driving. If you're drinking, call a cab, a car, or a friend. Bus driving is drunk driving. A message brought to you by NHTSA and the Ad Council. You know the legal drinking age is 21. You may also know this law protects teens. Find out more at DontServeTeens.gov. A message from the We Don't Serve Teens program and the Federal Trade Commission. You talk.