In this paper we report the realization and characterization of low-loss, capacitive RF MEMS switches that utilize folded serpentine spring suspensions with large area actuation electrodes. The surface micromachined switches with 1.7 μm thick, electroplated gold beams are implemented in standard 50 ohm CPW configuration. The electromechanical characterization indicates the measured actuation voltages in the range of 8 - 15 volts. The RF measurements of devices give insertion loss of 0.24 dB and isolation better than 21 dB at 20 GHz. © 2004 IEEE.