A seat assembly for a vehicle includes a seat bottom and a seatback. The seatback includes a seatback frame and is selectively rotatable relative to the seat bottom from an upright position to a forward position. A seatbelt assembly includes a retractor coupled to the seatback frame and a belt selectively extendable from and retractable to the retractor. A first end of the belt is disposed in the retractor. A guide is coupled to the seatback frame and defines an orifice with the belt slideably extending through the orifice. The retractor and the guide are fixed relative to the seatback frame and the second end of the belt is fixed to the seatback frame. The retractor, the guide, and both ends of the belt rotate from the upright position to the forward position in response to a force exerted on the seatback frame during rapid deceleration of the seat assembly.