DETROIT — Starting in September of 2027, all new passenger vehicles in the U.S. will have to sound a warning if rear-seat passengers don’t buckle up.
The National Highway Traffic Safety Administration said Monday that it finalized the rule, which also requires enhanced warnings when front seat belts aren’t fastened.
The agency estimates that the new rule will save 50 lives per year and prevent 500 injuries when fully in effect, according to a statement.
The new rule will apply to passenger cars, trucks, buses except for school buses, and multipurpose vehicles weighing up to 10,000 pounds.
Before the rule, seat belt warnings were required only for the driver’s seat. Under the new rule, outboard front-seat passengers also must get a warning if they don’t fasten their belts. Front-center seats will not get a warning because NHTSA found that it wouldn’t be cost effective. The agency said most vehicles already have warnings for the outboard passenger seats.
The rule also lengthens the duration of audio and visual warnings for the driver’s seat. The front-seat rules are effective starting Sept. 1 of 2026.