Seatbelts are estimated to reduce the overall risk for serious injuries in crashes by 60-70% and the risk for fatalities by about 45%. In rollovers, the risk of fatalities for a belted occupant is reduced by roughly 75%. It is estimated that more than a million people have been saved since seatbelts were first introduced in automobiles in the 1950s. The U.S National Highway Traffic Safety Administration (NHTSA) estimates that in the United States alone, seatbelts save more than 13, 000 lives annually, prevent over 300, 000 serious personal injuries and save $50 billion every year to the U.S society.
Seatbelts help reduce the risk of injury in many types of crashes. They help to properly position occupants to maximize the airbag's benefits and --unlike airbags-- they also protect occupants in multiple-collision crashes. Therefore, it is important that seatbelts always be worn, even in airbag-equipped vehicles.
The seatbelt is designed to stretch at a controlled rate to absorb crash energy and reduce the severity of the occupant's deceleration.