A switch device includes a housing having a case and a holding member, a moving member, a biasing member, a movable contact, a common fixed contact, a first switching fixed contact, a second switching fixed contact, extending portions, at least two terminal members, and resistors for obtaining the resistance value between two terminal members, and fixing portions to which the resistors are soldered. The holding member includes a bottom wall portion that covers the bottom of the case, and a holding wall portion holding the fixing portions. The holding wall portion is formed of a first synthetic resin material having heat resistance, and the bottom wall portion is made of a second synthetic resin material having a heat distortion temperature lower than that of the first synthetic resin material. A method for manufacturing a switch device includes a first molding step, a resistor mounting step, and a second molding step.