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3-Way Switch Wiring Diagram Variation #3

Wiring diagram for a 3-way switch, one of the many wiring diagrams showing different methods of wiring a three way switch circuit.  This electrical wiring diagram shows power into light switch Box #1 – wire to light from switch box #1, and from switch box #1 to three-way light switch box #2.

Note that in this case, a larger than normal device box is required at switch #1 location, due to box fill calculations (most regular size boxes will only accommodate five wires; in this situation, you will have seven wires).

NOTE:  This is a thumbnail diagram.  Click on it to enlarge it.

There are many variations for wiring a 3-way switch network.  See our wiring diagrams page for more ways to wire a three way switch circuit.

Need help understanding how a light switch (both single-pole and 3-way) works?  Watch this great video that shows how they work!

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  • shekumohamad


  • bob kind

    Thanks this first thumbnail diagram helped a lot. on other websights the screws were in the wrong place to the switches i had on hand your sight made it very easy………

  • Pf Doughty

    can I take power to another circuit from the second 3 way switch

    • Gee

      No, since there is no Neutral coming to that box.

  • steve

    can I use this diagram with wiring a series of lights?

  • Parkman

    Very good instructions, easy to follow, and the diagram – as the other posted said, made it absolutely easy to understand and match up to what I saw in the wall. Good on ya! Thanks.

  • Stephen

    All the diagrams show lights being powered off one switch. I have a light at the top of stairs with 3 way switch and a light at the bottom with a 3 way switch that has the power coming into it, 12-2 goes to each light from its nearest switch. How do we wire the bottom switch with power coming in, that also needs to power the bottom light. the 12-3 goes from the bottom switch to the top. All diagrams don’t show this senario.

  • JayWes38

    The National Electrical code now requires that the Neutral be wired to each switch location to allow for connection of pilot lights and dimmmers without using a ground wiere. This diagram also aomits the grounf wire.

  • Finleyriver1

     This is wrong.  Both black wires should go to the top screw which is also black called the common. do not follow this 3 way switch diagram variation #3 it wont work……

    • Wdowney647

      It will work. You should try it before you post something so wrong.

    • Badjeepr

      youre an idiot finley

    • Badjeepr

      It is in violation of the NEC…but it works

    • FarmerTim

      Whether these diagrams is correct depends on the configuration of your switch.  You can’t identify the common conducter (usually a black screw) based on these diagrams.    The hot wire (black) needs to attach to the common conducter of the first switch it connects to (in this case the right switch).  The black screw is not always in the same location relative to the other screws as is shown in the diagram.   Red and white wires connect the 2 brass screws on each switch (doesn’t matter how).  The common conducter (black screw) of the second switch (in this case on the left) should connect to the black wire that goes to the light.  All you need to remember is that if you consider the two switches to be a unit, then the common conducters bring power in and power out of the unit, then everything else falls into place.

    • Jfkopena

      the screw at the bottom by itself is the common

  • John

    This worked for me!

  • Duwaynecalkins

    i am trying to wire 2 switches from 1 power suply single switches please help

  • Arturofuca

    Off course I did the grounded ones  at the green screws. Realy apreciate your help  with this diagram now i can turn the light at the front door  and turn off at the back one.

  • Chad72994

    the Wiring Diagram  help me so much now 3-way is go to work

  • Jon

    I had two switches in my bath room, one runs a fan the other is the light, I put a  couple of 3 way switches and needed to know how to wire them, used your site, “job done” thank you


    Thanks this first thumbnail diagram helped a lot.

  • josh kopena

    this is decent if your wiring in conduit if your using romex your &%*#

  • Lsl – just bought an old house
    3 way would turn lights and fan on/off randomly
    One wire was just hanging there
    Your diagram was most helpful
    Wired it
    Still didn’t work right due to bad switch, which was why previous owner screwed it all up.
    Moral of the story
    If all else fails, test your switch! Or maybe test the switch first.
    Mine had power, light, and 4 way wire in first box, 4 way in second box.

  • patrick

    worked for me. This was the only diagram I could find with 2-conductor power coming in and the 2-conductor light in the same switch box. Other collections of diagrams omitted this variation.

  • Ewan

    Happy New Year all!… hoping for some help with variation #3.
    Would I be able to add additional lights in the middle of the 14/3 run between the 3-way switches?


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