US to Require Alarm If Rear-Seat Car Passengers Aren’t Buckled Up

Starting Sept. 1, 2027, an alarm will sound for up to one minute if rear-seat passengers aren't using their seat belts. Georgii Dolgykh/Photos.com

The federal government will soon require alarms that go off if car passengers in rear seats are not wearing seat belts, according to a new rule issued on Dec. 16.

The National Highway Traffic Safety Administration (NHTSA), part of the U.S. Department of Transportation, has finalized the updated motor vehicle requirements for seat belts, which the agency said could save 50 lives per year.

Under the rule, when the driver starts the vehicle, a visual warning is required informing the driver which seat belts are being used and which are not, provided that there are occupied rear seats and the system determines at least one passenger in the back is not wearing a seat belt. The warning must last for at least one minute.

The rule also requires an alarm for the front passenger seat next to the door, or the front outboard passenger seat. The warning for that seat must activate when a passenger is in the seat and not using a seat belt and last at least 30 seconds. A second phase activates whenever there’s a passenger in the seat, the person is not using the seat belt, and the vehicle is traveling at a speed of 6.2 miles per hour or more. The second phase remains in place until the seat belt is used.

The rule also requires that audio and visual warnings go off when any rear seat belts are unfastened while the vehicle is moving. That warning must go off for at least 30 seconds or until the seat belt is refastened.

Previously, the only required seat belt warning was for the driver’s seat, although many automakers have implemented warnings for the front passenger seat.

The center front passenger seat does not require a warning because it “would not be cost-effective,” the NHTSA said.

Automakers must start complying with the requirements for the front outboard passenger seat starting Sept. 1, 2026, and with the requirements for rear seat belts starting Sept. 1, 2027. The rules cover both gasoline-powered and electric vehicles.

“Wearing a seat belt is one of the easiest and most effective ways to prevent injury and death in a vehicle crash,” NHTSA chief counsel Adam Raviv said in a statement. “While seat belt use has improved for decades, there’s still more we can do to make sure everyone buckles up. These new requirements will help to increase seat belt use, especially for rear seat passengers, by enhancing reminders for vehicle occupants to buckle up.”

The NHSTA said the requirements will add costs to the manufacturing process but would reduce fatalities and injuries to passengers. An agency projection estimated the new rule would prevent more than 500 injuries and about 50 fatalities per year.

The Insurance Institute for Highway Safety had previously expressed support for stricter seat belt alarm requirements. The institute has estimated that about 1,500 fewer people would die in crashes per year if they were wearing seat belts.

The Alliance for Automotive Innovation, of which many major automakers are part, did not respond to a request for comment.