The invention provides a method for readily forming a bump with a desired width, a semiconductor device and a method for making the same, a circuit board, and an electronic device. A method for forming a bump includes forming an opening in an insulating film which exposes at least a part of a pad, and forming the bump so as to be connected to the pad. A resist layer 20 defines a through hole which extends over at least a part of the pad in plan view. A metal layer is formed in the opening so as to connect to the exposed portion of the pad.