A seat adjuster particularly adapted for motor vehicle seats. The seat adjuster enables fore-and-aft movement of the seat and also provides an anchorage point for a seat belt restraint system which moves with the seat during adjustment. The seat adjuster includes a fixed base adapted for attachment to the vehicle's floor pan which forms an elongated toothed rack. A sliding rail which moves along the base includes a latching mechanism. The latching mechanism has a latching plate which is movable vertically and includes engagement features which mesh with the toothed rack on the base. In the normal condition, the latching plate is in an upward vertically moved position in engagement with the toothed rack thereby setting the adjusted position of the seat and providing firm support for the seat belt anchorage attached to the latching mechanism. When adjustment is desired, a release bar is actuated which moves the latching plate downward thereby disengaging the engagement features. The seat adjuster mechanism accordingly combines the functions of the seat adjuster and seat belt anchorages to provide an efficient and structurally secure seat adjuster.