The present invention generally relates to the formation of a micro-electromechanical system (MEMS) cantilever switch in a complementary metal oxide semiconductor (CMOS) back end of the line (BEOL) process. The cantilever switch is formed in electrical communication with a lower electrode in the structure. The lower electrode may be either blanket deposited and patterned or simply deposited in vias or trenches of the underlying structure. The excess material used for the lower electrode is then planarized by chemical mechanical polishing or planarization (CMP). The cantilever switch is then formed over the planarized lower electrode.