In New Hampshire, you must be at least 21 years old to gamble legally. This age requirement applies to all forms of gambling, including casinos, poker rooms, and lottery tickets. It is important to have a valid form of identification to prove your age when participating in any gambling activities. New Hampshire strictly enforces age restrictions to prevent underage gambling and protect young individuals from potential harm. Make sure to always adhere to the legal age requirements for gambling in New Hampshire to avoid any penalties or consequences.