Seat belts became mandatory in the United States on Jan. 1, 1968, by passage of federal law Title 49 of the United States Code, Chapter 301, Motor Vehicle Safety Standard. This law was for all vehicles, with the exception of buses.
The federal law mandating seat belts has since been modified to include the type of seat belt and in which position it is to be fitted. The law has also undergone different amendments at the state level. Current seat belt laws vary by state in type of offense, terms of enforcement, fines and the ages for whom the law applies.