You have to be at least 18 years old to enter a casino and participate in gambling activities. Different countries and states may have varying age restrictions for entering a casino. It is important to check the legal age requirements in the specific location you plan to visit. Casinos typically require guests to provide valid identification to verify their age before entering the premises. Underage individuals are not allowed in the gaming areas of a casino. Always make sure to adhere to the age regulations to avoid any legal consequences.