The National Highway Traffic Safety Administration (NHTSA) has made rear seat belt alerts mandatory starting from September 1, 2027.The rule requires visual and auditory alerts to the driver if a passenger is detected in a rear seat unbuckled.Front-seat occupants will also receive updated warnings, including a two-stage audible warning upon starting the vehicle.NHTSA estimates that 50 lives annually can be saved with rear-seat and enhanced front-seat warnings.