A keypad lockset adapted for deadbolt as well as lever locks, and having as a first embodiment an exterior gear train, an interior gear train, and an electronically controlled clutch for coupling the gear trains when engaged and for uncoupling the gear trains when the clutch is disengaged, so that when the clutch is engaged rotation of an external thumb turn will permit the door latch to be withdrawn and thus to permit opening of the door, and a mechanical override mechanism that can be operated in case of electrical failure, and in which clutch mechanism and the override mechanism both operate through the single, standard 2⅛ inch door preparation hole, or alternatively as a second embodiment, a keypad lockset in which two four-bar mechanical linkages are used in place of gears as means to actuate the clutch, and alternatively to provide for a pass-through override function.