What is the legal age to drink/gamble/drive in Las Vegas and California?
The other answers are correct and you have to be age 21 in all of the USA to legally purchase alcohol (beer, wine, spirits, drinks, bottles, cans, in bars, at restaurants, in stores – it doesn’t matter, you still have to be 21 or older). To my knowledge, the age to gamble is also 21 in all of the USA. There may be casinos on Indian (“Native American”) reservations that allow age 18 but I doubt it. Most car rental companies in the USA require the primary driver to be age 25 or older, but that is a policy and not a law. Check with travel agencies to find rental companies that accept primary drivers under the age of 25. Good luck!
