You need to be at least 21 years old to enter a casino in most US states. Some states allow entrance at 18 for specific activities like bingo or poker. Make sure to check the legal gambling age in your state before planning a casino visit. Age verification is strictly enforced at casinos to ensure compliance with regulations. Always carry a valid ID to prove your age when visiting a casino. Remember, underage gambling is illegal and could result in fines or other penalties.