Switch wiring diagrams

Use these switch wiring diagrams to help you figure out the wiring in your home.

Switch wiring diagrams can help you understand electrical circuit better and they also help you trouble shoot problems in your electrical circuit.

Wiring diagram for how to wire a 3 way switch.

This is the easiest way to wire a 3 way circuit. Power (line in) one switch box and switch leg (load) out of the other switch box and a 3 wire with ground between the two boxes.

You could add outlets to this circuit but you would need to come out of the first switch box on the left, it’s the only box that has a consistent power source. Refer to last diagram on this page. “1 single pole switch with 2 outlets” to see how this is done.

 

Wiring diagram for how to wire a dead end 3 way switch.

This method is a bit more confusing way to wire a 3 way circuit. You have the power (line), switch leg, and 3 wire with ground in one box and just a 3 wire with ground in the other box. You have to send power to the second box using the white/taped black wire and send it back using the black and red traveler wires. Remember to always use black or red tape on both ends of the white wire you are using for power. In this case between the two switch boxes.

Add outlets to this circuit by coming out of the first box with romex. This is because it’s the only switch box that has a constant power source. Refer to last wiring diagram on this page for more info. “1 single pole switch with 2 outlets”

 

4 way switch wiring diagram

 

Here is a wiring diagram for wiring a 4 way switch. A 4 way switch is used to add more locations to turn on a light. You would start to add 4 way switches if you have 3 or more locations that you want to turn a light on. Each brand of 4 way switches are a little different in the way they are wired. With some brands they put the pairs at the top and some the pairs are on the side. The back of the switch should say how they are wired.

If you were to add outlets to this circuit you would need to come out of “Box A” It’s the only box that has a consistent power source. For more info on how to do this refer to last diagram on this page called “1 single pole switch with 2 outlets”

 

4 way switch wiring diagram (dead end)

Don’t get overwhelmed by this one. At first glance it can look intimidating. If you follow the color coding it will make sense.

This method may be even more confusing way to wire a 3 way/4 way circuit. You have the power (line), switch leg, and 3 wire with ground in “Box A”, 3 wire with ground in and out of “Box B” and just a 3 wire with ground in “Box C”. You have to send power through “Box B”  using the white/taped black wire through to “Box C”. In “Box C” the white/taped black wire goes through the switch and send power back using the black and red traveler wires. Remember to always use black or red tape on all ends of the white wire you are using for power. In this case between the three switch boxes.

Add outlets to this circuit by coming out of the first box with romex. This is because it’s the only switch box that has a constant power source. For example refer to last diagram on this page called “1 single pole switch with 2 outlets”

 

Wiring diagram single pole switch with 2 outlets

 

This wiring diagram shows how a single pole switch is wired with two outlets. Multiple outlets can be added by duplicating the wiring shown on the bottom left of the picture above.

 

Need more information?

How to wire a 3 way switch

How to wire a single pole switch

How to wire an outlet

How to wire a GFCI

How does a GFCI work

Outlet wiring diagrams