MULTIPLEXER

A multiplexer includes: first and second substrate respectively having first and second surfaces facing each other across an air gap; a first filter including first resonators located on the first surface and connected between a common terminal and a first terminal; a second filter including second resonators located on the second surface and connected between the common terminal and a second terminal, a first resonator connected in series between the common terminal and the first terminal and closest to the common terminal overlapping with a second resonator connected in series between the common terminal and the second terminal and closest to the common terminal, first resonators other than the first resonator closest to the common terminal not overlapping with the second resonators, second resonators other than the second resonator closest to the common terminal not overlapping with the first resonators.