The present disclosure provides systems, components, and methods for leveling millwork. In one or more implementations, a millwork leveling device and/or kit for leveling millwork include a track, a first leveling post, and a second leveling post. The leveling posts are movably positionable along the track. The first leveling post has a first adjustable height and the second leveling post has a second adjustable height. The device and/or kit may further include a plate associated with the first leveling post, the plate having one or more through holes and attaching a finishing piece thereto.