Change a Single Pole Switch

Single wire switch wiring
DonNichols / Getty Images

From time to time electrical switches will wear out from years of being flipped on and off. This how-to article will teach you why switches don’t work and how to correct the problem. Learn how to safely replace a broken or outdated switch like a professional.


Difficulty: Easy

Time Required: Less than thirty minutes.

Here's How:

  1. Reasons for Changing a Switch                                                                                                                                                              

    There are four main reasons to change a single pole switch.


    1. One is obvious. It doesn’t work anymore.
    2. Another reason may be you’ve updated the lighting in your home and increased the load on the circuit.
    3. If you have ever turned a switch on and it sizzled or popped, you now know the third reason. The contacts in the switches are subjected to endless flipping on and off. Over time, these contacts become worn and, hence, the sizzling and popping.
    4. The last is because your old switch may not be grounded. Always use a grounded switch when replacing switches.


  1. Safety First - Turn Off the Power First                                                                                                                                                                                                                         Broken switches can short out, leave you susceptible to live parts and increase the chance for electrical shock. As with any electrical repair you may perform, safety should be your number one concern. Turn off the circuit you will be working on and double-check it with a circuit tester or voltmeter. Never assume the circuit is off! Go directly to the fuse box or circuit breaker panel and look at the chart for circuit location. Once found, turn the circuit breaker off or unscrew the fuse. It's best to remove the fuse completely.                                                    
  2. Removing the Old Switch                                                                                                                                                                                                                                Remove the switch cover plate by removing the two screws. Turn the screws counterclockwise and remove the switch cover. The switch is now exposed. Remove the two screws holding the switch in place and carefully pull out the switch. This is the time to take the tester once more and triple check to see if the circuit is off. Test from the green ground screw or the metal box to the two brass screws on the switch. If there’s no power then you can continue. Loosen the two brass screws and the ground screw. Remove the switch and discard it.                                                                                                     
  1. Connecting the New Switch                                                                                                                 

    Bend the ends of the wire into a half moon shape to go around the screws. First tighten the bare copper or green wire to the green ground screw. Always tighten the half moon shape towards the right and in a clockwise motion. This will insure that the connection is good and tight. The loop of wire should wrap the screw from left to right. As you tighten the screw on the wire, the loop should tighten. Next connect the two black wires to the remaining brass colored screws in the same way. Tug on each wire and make sure the connection is tight.


  1. An Added Safety Feature                                                                                                                                         

    Once the connections are secure, I like to wrap the switch with electrical tape as an added safety measure. This eliminates the switch from coming into contact with the side of the box. Be sure to cover the entire set of screws on the switch. Now, press the switch into the box for a test fit. You may have to adjust the wires in the box to make everything fit. Tighten the two screws into the box, keeping it as plumb as can be. watch the wires in the box as you tighten the switch screws, as not to damage the wires. Replace the switch cover and tighten its two screws. Now take a level and level the switch cover for a nice appearance. There, you have done it!


  2. Turn Power Back On                                                                                                                                                   

    Turn on the circuit at the breaker panel or fuse box and test the circuit to see if everything is working. Be sure the fuse is screwed in tightly for a secure connection. You can simply turn on the light switch and see if the light works If so, you have completed your “light duty” of the day!


    What You Need: