The invention concerns an adaptable electromagnetic actuator for an electric switch, comprising a mobile coil (15) and a main magnetic circuit (20) consisting of an external yoke (21) and a core (22) made of magnetic material, and of a magnet (25) with radially oriented polarization inserted between the yoke (21) and the core (22). The yoke (21), the core (22) and the magnet (25) form a base (23) of the magnetic circuit (20) which is capable of receiving one or more additional stackable modules (20, 40) consisting each of an additional magnet (35) with radially oriented polarization inserted between an additional core (32) and an external additional yoke (31).