Composite electronic component

A composite electronic component, comprising:

• a first acoustic wave filter;
• a second acoustic wave filter that faces the first acoustic wave filter in a first direction;
• a spacer layer having a substantially frame shape and provided between the first acoustic wave filter and the second acoustic wave filter in the first direction;
• and
• a switch that switches an ON state and an OFF state of the first acoustic wave filter and an ON state and an OFF state of the second acoustic wave filter;
• wherein
• the first acoustic wave filter includes:
• a first support having piezoelectricity at least in a portion thereof;
• and
• a first functional electrode provided at a first principal surface of the first support;
• the second acoustic wave filter includes:
• a second support having piezoelectricity at least in a portion thereof;
• and
• a second functional electrode provided at a second principal surface of the second support;
• a hollow space is defined by the first support, the second support, and the spacer layer;
• the first functional electrode and the second functional electrode are located in the hollow space and face each other in the first direction;
• and
• the switch brings at least one of the first acoustic wave filter and the second acoustic wave filter into the OFF state.