The MEMS cantilever actuator is designed to be mounted on a substrate. The actuator comprises an elongated hot arm member having two spaced-apart portions, each provided at one end with a corresponding anchor pad connected to the substrate. The portions are connected together at a common end that is opposite the anchor pads. It further comprises an elongated cold arm member adjacent to and substantially parallel of the hot arm member, the cold arm member having at one end an anchor pad connected to the substrate, and a free end that is opposite the anchor pad thereof. A dielectric tether is attached over the common end of the portions of the hot arm member and the free end of the cold arm member. This MEMS actuator allows improving the performance, reliability and manufacturability of MEMS switches.