Except for New Hampshire, all states and the District of Columbia require adult front-seat occupants of motor vehicles to use seat belts. Adult rear-seat passengers are also covered by the laws in 31 states and the District of Columbia. Children are covered by separate laws.

State seat belt laws are divided into two categories: primary and secondary. Primary seat belt laws allow law enforcement officers to stop a motor vehicle and to issue a ticket or citation to a driver or passenger for not wearing a seat belt without any other traffic offense having occurred. Secondary seat belt laws only allow law enforcement officers to issue a ticket or citation for not wearing a seat belt when there has been another traffic offense by an occupant of the vehicle for which the occupant may be issued a ticket or citation.

In Mississippi (MS), the state enforces primary seat belt laws for front-seat occupants, meaning that law enforcement officers can stop a vehicle and issue a citation to the driver or passengers for not wearing a seat belt even if no other traffic offense has occurred. This law applies to all adult front-seat occupants. For rear-seat passengers, Mississippi does not currently require adults to wear seat belts, and thus they are not covered by primary or secondary seat belt laws. However, Mississippi has specific child restraint laws that require appropriate car seats or booster seats for children depending on their age, height, and weight. These child restraint laws are also primary enforcement, allowing officers to stop a vehicle solely for a child restraint violation.