How to Replace a Light Switch

Easy way to change a standard single-pole wall switch

Single-pole light switch being replaced from wall outlet box

The Spruce / Kevin Norris

Project Overview
  • Working Time: 45 mins
  • Total Time: 45 mins
  • Skill Level: Intermediate
  • Estimated Cost: $2 to $8

Learning how to replace light switches in your home is a useful skill and can be somewhat simple, especially when they are single-pole switches that control a light fixture or outlet from a single wall location. Because they get so much use, wall switches eventually wear out and need replacement. If a wall switch has lost its snap or feels loose, if you notice buzzing or crackling when you operate it, or if it fails to control the light fixture, it's time to replace the switch. Or, you may want to update the look of your switches from toggle to rocker-style. Read on to learn the simple steps to replacing a single-pole light switch.

Light Switch Wiring

Replacing a light switch is usually a straightforward matter of disconnecting two hot wires from the old switch and reconnecting them to a new switch. For a basic single-pole switch, you don't even need to pay attention to which hot wire gets attached to which screw terminal—they are interchangeable. The key is to simply pay attention to which wires are attached to the switch, and make sure they are attached in the same way to the new switch.

All new switches you purchase will have a green grounding screw on the mounting strap. When replacing an old switch, you will need to connect the new switch to the circuit ground wires, even if your old switch did not have a grounding connection.

Before You Begin

Turn off the power by switching off the circuit breaker that controls the circuit feeding the switch. In older systems that have fuse panels rather than circuit breakers, the power is turned off by unscrewing the fuse that protects the circuit you are working on.

Return to the wall switch and flip the switch to confirm that the power has been turned off. If not, return to the panel to locate and turn off the correct circuit breaker.

Safety Considerations

Make sure that the corresponding breaker for the switch you are replacing is confirmed to be off. You can even use a voltage tester to guarantee this. Additionally, confirm that the switch wiring is in good shape before making any changes, and finally, make sure that the new switch is compatible. When in doubt, seek professional assistance.

What You'll Need

Equipment / Tools

  • Screwdriver
  • Non-contact circuit tester
  • Wire cutters (optional)
  • Wire stripper (optional)
  • Needlenose pliers

Materials

  • Single-pole wall switch
  • Electrical tape (optional)
  • Grounding pigtail (optional if needed)
  • UL-rated wire connector (optional)

Instructions

How to Replace a Single-Pole Light Switch

Materials and tools to replace a single-pole light switch

The Spruce / Kevin Norris

Circuit breaker panel power switched off.

The Spruce / Kevin Norris

  1. Remove the Cover Plate and Test for Power

    • Remove the wall switch's cover plate by removing the mounting screws.
    • Test for power using a non-contact circuit tester. Insert the probe of the tester into the box alongside the screw terminals on the switch. The tester will light up or make a sound if there is live current in the box.
    Wall switch's cover plate removed and tested for power with non-contact circuit tester

    The Spruce / Kevin Norris

  2. Extract the Switch

    • After verifying that the power is off, remove the strap mounting screws that hold the switch to the box.
    • Carefully extract the switch by pulling outward on the straps.
    • Be careful to avoid stressing the wires. Old wires may be brittle and the insulation can crack if you're not careful.
    Switch extracted from switch box by pulling on straps.

    The Spruce / Kevin Norris

  3. Examine the Wires

    Take note of how the wires are connected to the switch:

    • In newer wiring made with NM cable, the wires will have black insulation and likely will be attached to brass or copper-colored screw terminals along one side or on opposite sides of the switch body.
    • In some configurations (known as a switch loop), the switch may be connected to a black and a white wire that has been marked with black tape to indicate that it serves as a hot wire.
    • There may also be a green grounding screw attached to bare copper circuit grounding wires, but this is not always the case.
    • With an older switch, the wires may have rubber or cloth insulation without any color coding.
    • Modern practice is to label these wires with black tape to identify them as hot wires. If they are not color-coded, it is a good idea to do this now.

    Tip

    If your wall switch has three or four insulated wires connected to it rather than two, you are not looking at a standard single-pole switch, but rather a 3-way or 4-way switch.

    These switches are used to control a light fixture from two or more wall locations. You can still replace this switch, but you will need to make sure you install the proper type of switch, and you will need to be very careful to connect the wires in exactly the same way they are connected to the old switch.

    Wires wrapped on side of switch with grounding screws being examined

    The Spruce / Kevin Norris

  4. Disconnect and Remove the Switch

    • Extract the switch far enough out of the box that you can reach the screw terminals with a screwdriver.
    • Disconnect the circuit wires.
    • Examine the wire loop at the end of each wire. If it is nicked or damaged, snip off the damaged portion of the wire, then strip about 3/4 inch of insulation to expose new copper wire.
    • If the switch has a grounding screw attached to circuit ground wires, also unscrew this connection.
    Circuit wires unscrewed on side of switch

    The Spruce / Kevin Norris

  5. Attach a Grounding Pigtail (If Needed)

    • Attach a grounding pigtail to the circuit grounding wires if your old switch had no grounding connection. The other end of the pigtail will be connected to the grounding terminal on the switch.
    • Grounding pigtails are available as short green-insulated wires designed for this purpose, or you can create your own grounding pigtail by using a short length of bare copper or green insulated wire.
    • Connect one end of this grounding pigtail to the grounding circuit wires in the box. Usually, this involves removing the wire nut that is joining the circuit grounding wires, then bundling the end of the new pigtail to those wires, and screwing the wire nut back on again.
    Grounding pigtail and grounding circuit wires bundled in orange cap

    The Spruce / Kevin Norris

  6. Connect the New Switch

    Make the wire connections. Connecting the new switch is a matter of making three wire connections: the grounding pigtail, and two hot wire connections.

    • Form a clockwise, C-shaped loop at the end of each wire.
    • Attach the free end of the grounding pigtail to the green grounding screw on the strap of the switch.
    • Loop the wire around the shaft of the screw, then tighten it down firmly.
    • Attach the two hot wires to the screw terminals on the side of the switch body.
    • Tighten the screws fully and tug on them to make sure they are secure.

    Tip

    In older homes that have metal boxes, it can be advantageous to wrap the newly connected switch with electrical tape to cover the connection points and wires. This helps avoid shorting out the circuit, something that can occasionally happen with old wires and metal boxes.

    New switch connected to hot wires and pigtails wrapped around screw shaft

    The Spruce / Kevin Norris

  7. Install the Switch and Cover Plate

    • Tuck the wires gently into the wall box.
    • Secure the switch with the mounting screws threaded into the holes onto the box.
    • Make sure the switch is positioned right-side-up so that the ON/OFF marking reads correctly.
    • Carefully align the switch so it is vertical in the box, then attach the cover plate.
    • Turn on the power to the circuit at the circuit breaker box.
    • Test the operation of the switch.
    Cover plate screwed over new switch with mounting screws

    The Spruce / Kevin Norris

Dimmer Switches

A dimmer switch can change the ambiance of a room, providing a range of light. Many dimmer switches can be installed in a standard wall box opening, replacing a typical switch. As usual, confirm without a doubt that the power to the switch is off before installing a dimmer switch.

When to Call a Professional

Replacing a wall switch ranks among the easier home electrical repairs, but any time you are working with electricity, there is the potential for shock. If you are not comfortable troubleshooting or attempting basic electrical work, it will be best to call an electrician to do this job. And don't be afraid to call a pro if you begin the repair but find that circumstances aren't what you expected.

FAQ
  • Can I replace a light switch myself?

    Replacing a light switch is a project best done by a DIYer with experience in electrical repairs and some understanding of circuits.

  • Can I change a light switch without turning off the power?

    Though it is possible for DIYers highly experienced with electrical work, it is not typically advised to change a light switch with the power on. It is strongly recommended that you turn off the power when changing a light switch.

  • How much labor does it take to replace a light switch?

    Calling in an electrician to replace a light switch can cost an average of $150, or between $100 and $200, depending on factors, such as where you live and the scope of the job.

The Spruce uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. How Much Does It Cost To Install A Light Switch? HomeAdvisor.