A switch device that includes a first input terminal that is connected to a first battery; a second input terminal that is connected to a second battery; a first output terminal that is connected to a first load; a second output terminal and a third output terminal that are both connected to a second load; a first conductive path that is connected to the first input terminal; a first switch that includes one terminal that is connected to the first input terminal via the first conductive path, and further includes another terminal; a second conductive path that is connected to the second input terminal; and a second switch that includes one terminal that is connected to the second input terminal via the second conductive path, and further includes another terminal.