Jun 02 , 2020

How to Wire a 3-Way Light Switch

Wiring a 3-Way Light Switch

Wiring a 3-way light switch is certainly more complicated than that of the more common single-pole switch, but you can figure it out if you follow our 3-way switch wiring diagram.

With a pair of 3-way switches, either can make or break the connection that completes the circuit to the light. The whole wiring a light switch project can be completed in a few hours if you don’t have to do any drywall removal and repair.

Keep reading and learn how to wire a light switch. Also, use the 3-way switch wiring diagram to learn light switch wiring.

For a Visual Walkthrough of How to Wire a 3-Way Light Switch, Watch this Video:

Family HandymanHow to Wire a 3 Way Light Switch

Directions for Wiring a 3-Way Light Switch Yourself:

To add the switch, you’ll use one of two wiring a light switch diagrams (shown below), depending on whether the power comes to your light switch first (the most common situation) or to the light fixture first. Either way, complete these five steps for 3-way light switch wiring:

  • Turn off the correct circuit at your electrical panel.
  • Add an electrical box for the second 3-way switch in the basement.
    • Pro tip: It’s likely you’ll also need to replace the existing switch box with a larger one to accommodate the extra wires for the 3 way switch.
  • Feed a length of 14-3 type NM cable (or 12-3, if you’re connecting to 12-gauge wire) between the two boxes. The 14-3 cable has three insulated conductors: white, black and red (plus a bare ground wire).
  • Connect the wires to the new 3-way switches with ground screws using one of the two wiring diagrams (Fig. A or B).
    • Pro tip: The switches will be identified by a label on the common terminal and/or the terminal screw will be a different color.
  • Make sure to wrap black electrical tape around the ends of all white wires used as travelers between the 3-way switches. If you have the setup shown in Fig. A, also wrap black tape around the white wire from the switch to the light.
    • Pro tip: This way, you and others will know these wires are “hot” and not neutral like most white wires.
If you have aluminum wiring, call in a licensed pro who’s certified to work with it. This wiring is dull gray, not the dull orange that’s characteristic of copper.

Related Posts

How to Make an Extra $1,000 Per Month in Just 5 Hours Per Week With a Part Time Handyman Business
The handyman business works great as a part-time business. The overhead is low and it only takes a few hours per week...
Read More
What’s the Best Way to Advertise for a Handyman Business?
Pros are always asking me for the best way to advertise their handyman business. Is it Home Advisor? Thumbtack? Craig...
Read More
Thumbtack Pro Review: What You Need to Know
Thumbtack can be a fast and easy way to get customers and grow your business, but should you use this lead generation...
Read More