SEAT DEVICE

A seat device for a vehicle includes a seat for supporting a lower body of a vehicle occupant, and a backrest for supporting an upper body of the occupant. The seat device further includes an arresting portion that is stored in a storage position disposed in the seat. The arresting portion is configured to be deployed from the storage position and restrain a part of the lower body of the occupant from moving forward in the event of a collision of the vehicle.