How to Replace a Light Switch

Sick and tired of that one light switch that always seems to be flickering? Ready to tackle that new three-way switch in your den? Let Home Matters shed a little light on how to safely, quickly and easily tackle this common DIY project. Let’s start by identifying your wires and accessories for installation. 

Safety First - Cut the Power

First and foremost, before tackling any electrical work, you’ll want to locate your electrical panel and shut off the correct circuit. If you have an older house, you may have dated wiring. Take a quick peek at our handy article on identifying issues with old wiring.

Know Your Wires

If this is your first time tackling a light switch – label your wires. There is no shame in playing it safe. Also, if at any point during this process you feel unsure of things – stop what you’re doing. There’s also no shame in admitting you’re intimidated by things—or even anxious about dealing with electricity. If you’re feeling unsure, do not hesitate to call a local electrician.

Ground Wire – The ground wire is your friend. It sounds silly to say, but this bare wire protects you from electric shock by maintaining the voltage in the circuit. Also, the ground wire is what causes your circuit breaker to trip should the voltage get excessive.

Hot Wire – This black wire lives up to its name as it is the path of voltage from your power source to your light. 

Neutral Wire – Your neutral wire is white and connects to both your source and the ground.

Traveler Wires – These red wires connect your switches together in a multiple switch system. 

Wire Nuts – You’re going to want to have items on hand as these twist-on connectors link two or more wires.  

Related: How to Change a Light Socket

How to install a One-Way Switch

New to light electrical work? A little anxious about diving into DIY projects? The one-way switch is for you. This switch is fairly common and is found in most bathrooms or hallways. Simply put, the one-way switch applies to lights that are turned on and off with just one switch. 

Step 1: Unscrew and remove your switch plate.

Step 2: Unscrew the switch from the electrical box and remove it. Keep all of the wires attached.

Step 3. Compare your new switch to the one you’re replacing. Find the corresponding connectors. Feel free to write down which wires go where. 

Step 4: Connect the first wire you remove to the same color screw on your new electrical box. To do this, use wire strippers to remove about a half an inch of insulation and wrap the exposed wire around the terminal screw. Repeat this process with your second wire. 

Step 5: Insert your new electrical box and screw into place

Step 6: Screw on your switch plate and turn your power back on.   

How to Install a Three-Way Switch

When it comes to installing switches, a three-way switch is more involved than the traditional single switch, but it's nothing you can’t handle with a little time and patience.

Step 1: Unscrew and remove your switch plate.

Step 2: Unscrew the switch from the electrical box and remove it. Keep all of the wires attached.

Step 3: Compare your new switch to the one you’re replacing. Find the corresponding connectors. Feel free to write down which wires go where.

Step 4: You’re going to see more wires in a three-way switch. Depending on whether or not there is a ground wire, you could see as many as four. Deep breath. You got this. 

Step 5: Remove the wires from the switch. Note: your new switch may have connectors in different locations.

Step 6: At the top of your switch, you will find two brass terminals. At the bottom, you can expect to find a dark screw terminal. Mark all of your wires with tape and remove them from your existing switch.

Step 7: Attach your labeled wire to the corresponding positions on your new switch. Note: if you have a ground wire, connect it to the green screw terminal on your new switch or the electrical box. 

Step 8: Insert your new electrical box and screw into place.

Step 9: Screw on your switch plate and turn your power back on. 

Installing a new light switch is a great DIY project to get some experience with basic wiring, but maybe you’re starting to wonder about bigger, more elaborate electrical issues with your home? Get Home Electrical Warranty System Coverage from American Home Shield® and get coverage of major components of many home systems, including your electrical system, and this coverage picks up where your homeowner's insurance policy leaves off. The AHS Home Warranty Plan provides broad coverage of many common electrical malfunctions.