Disclosed is a capacitive electrostatic MEMS RF switch comprised of a lower electrode that acts as both a transmission line and as an actuation electrode. Also, there is an array of one or more fixed beams above the lower electrode that is connected to ground. The lower electrode transmits the RF signal when the top beam or beams are up and when the upper beams are actuated and bent down, the transmission line is shunted to ground ending the RF transmission. A high dielectric constant material is used in the capacitive portion of the switch to achieve a high capacitance per unit area thus reducing the required chip area and enhancing the insertion loss characteristics in the non-actuated state. A gap between beam and lower electrode of less than 1 &mgr;m is incorporated in order to minimize the electrostatic potential (pull-in voltage) required to actuate the switch.