Wiring Diagrams for 3-Way and 4-Way Switches

A three way switch allows for controlling a light fixture from two locations. These are usually used at the top and bottom of a flight of stairs or at two different entrances to a room. Below are three options for wiring a three way switch depending on the location of the light fixture in relationship to the electricity source. Another option for controlling a fixture from three or more locations is a four way switch. A wiring diagram for a four way switch circuit is shown at the bottom of this page. Use 14|3 cable between the switches and 14|2 cable to the light fixture in these diagrams.

Electricity source before the light fixture and the two switches after.

Electricity source at first switch and light fixture between the two switches.

Electricity source at first switch and light fixture at the end of the circuit.

Wiring 4-Way Switches

Wire a 4-Way Switch in combination with two 3-way switches to control a fixture from three locations. A 4-way switch has four terminal screws divided into two matching pairs. The pairs may be on opposite sides of the switch, as in this diagram, or they may be on the same side of the switch. Each pair of screws should be wired to each 3-way switch. Don't mix up the pairs or the circuit won't work correctly.