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Automatic seat belt in a Honda Civic

Automatic seat belts are seat belts that automatically close over riders in a car.

Automatic seat belts were created to increase safety regardless of user negligence because even when seat belts were available, people often forgot to, or chose not to, use them.

The 1972 Volkswagen ESVW1 Experimental Safety Vehicle presented passive seat belts ^[1]. Volvo tried to develop a passive three point seatbelt. In 1973 Volkswagen announced they had a functional passive seat belt^[2].

One problem identified with the automatic seat belt is that they do not work well with child safety seats. When air bags became mandatory, most vehicles stopped offering automatic seat belts. The biggest exception is the Ford Escort/Mercury Tracer, as well as a few other models, which continued using automatic safety belts along with dual airbags in the 1995 and 1996 model years.

• Manual lap belt with automatic shoulder belt — When the door is opened, the shoulder belt moves from a fixed point on a track mounted in the door frame of the car to a point at the end of the track. Once the door is closed, and the car is turned on, the belt retracts along the track to a fixed position at the other end of the track. The lap belt must be fastened manually. A drawback of this system is that many users forget to fasten the lap belt. A special seat belt modification is needed to use child seats in the front seats in vehicles fitted with this type of safety belt system.

• Automatic Shoulder and Lap Belts — This system was mainly used in older General Motors vehicles. When open, the belts go from a fixed point in the middle of the car by the floor to retractors on the door. Passengers must slide into the car under the belts. When the door closes, the retractors travel down the door. The maneuver required to slide out from these seat belts is awkward, and likely to knock off glasses if the person is wearing them, fortunately the seat belts have normal release buttons that are supposed to be used only in an emergency but in practice are routinely used in the same manner as manual seat belt clasps. Any child safety seats in vehicles using this type of automatic seat belts used must be installed by a dealer.

• The seatbelt is activated by a motor at the base of the "B" pillar and has a cable wrapped in a hard plastic coating.^{[citation needed]} Over repeated use, the plastic casing cracks and eventually causes the cable to jam, leaving the seatbelt latch halfway in the doorway, rendering the shoulder seatbelt useless and not safely deployed in an impact.^{[citation needed]} Manufacturers who use this seatbelt do not offer a warranty for replacement because of the vehicles age and replacement parts have been known to range around USD$400-$500.^{[citation needed]}

• In a collision where the structural metal surrounding the passenger compartment deforms, causing doors to pop open, this type of seatbelt may not fully keep the front passenger secured inside the vehicle.^{[citation needed]} The collision can be from the front or from the side. There are brackets attached to the inside door jamb that are designed to grab corresponding brackets on the door to prevent the door from opening, but they are not 100% effective, based on the conditions of the collision.^{[citation needed]}

1. ^ [1]
2. ^ PDF, Safety sells, Page 50