Every state except New Hampshire has a seat belt requirement for adults. All 50 states and the District of Columbia have seat belt laws that cover children. These laws require children under a certain age (usually 3 or 4) to be placed in a child restraint (a baby seat, a booster seat, etc.); buckling these children up with adult belts is not permitted by law.

New York is one of the most active proponents of seat belt regulation. It was the first state to try to pass seat belt legislation when in 1959 it tried to mandate seat belts in all new cars sold in the state. In 1985, New York made seat belt use mandatory for back seat passengers aged 10 or older; in 1987 it became the first state to require seat belts on large school buses.