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 Illinois, the state enforces primary seat belt laws for both front-seat and rear-seat occupants. This means that law enforcement officers have the authority to stop a vehicle and issue citations to drivers and passengers solely for not wearing seat belts, without the need for any other traffic violation to have occurred. Illinois law requires all front-seat occupants to wear seat belts. Additionally, the law extends to rear-seat passengers as well. For children, Illinois has specific child restraint laws that mandate appropriate safety seats and restraints for children of certain ages and sizes. These laws are designed to ensure the safety of all vehicle occupants and to reduce the risk of injury or death in the event of an accident.