Device for attaching a license plate to a vehicle

The device for the fastening of a number plate (1) to a motor vehicle has a mounting (2) provided on the vehicle and an electric heater (9) for the number plates connected to the vehicle's electric power supply. The electric heater which is provided on a support (8) between the number plate and the mounting is controllable in dependence upon at least one temperature sensor located in the mounting area. Heat insulation (10) is provided on the heater side facing away from the number plate.