What You Need to Do Before You Start
Replacing a GFCI outlet (ground fault circuit interrupter) is a task most homeowners can do in under an hour with basic tools. The outlet itself costs between $10 and $25, and you will need a screwdriver, a voltage tester, and wire strippers. Before you touch anything, turn off the breaker that controls that outlet at your electrical panel, then use a voltage tester on the outlet to confirm the power is actually off. This step takes 30 seconds and prevents electrocution.
GFCI outlets protect you from electrical shock by detecting imbalances in current flow — they trip faster than a standard breaker when water is involved. If your outlet is in a bathroom, kitchen, garage, or within 6 feet of a sink, it should be a GFCI. If the outlet you are replacing is not one but should be, now is the time to install one.
Key Takeaways
- Turn off the breaker at your panel and test the outlet with a voltage tester before removing anything.
- Remove the old outlet by unscrewing the two terminal screws and pulling the outlet straight out, then disconnect the wires by loosening the screws on the back or sides.
- Connect the new GFCI outlet by attaching the black (hot) wire to the brass screw, the white (neutral) wire to the silver screw, and the bare copper (ground) wire to the green screw.
- Push the outlet back into the box, screw it in, attach the cover plate, turn the breaker back on, and test the outlet using its built-in test button.
Remove the Old Outlet
Once the breaker is off and you have confirmed no power is reaching the outlet, unscrew the two screws that hold the outlet to the electrical box — one at the top and one at the bottom of the outlet face. These screws are usually Phillips head and sit in the center of the outlet. Pull the outlet straight out of the box. Do not yank on the wires; they should come out with the outlet.
Now disconnect the wires. You will see three wires attached to the back or sides of the outlet: a black wire (hot), a white wire (neutral), and a bare copper wire (ground). Loosen the terminal screws — usually by turning them counterclockwise — until the wires come free. If the wires are pushed into holes on the back of the outlet instead of wrapped around screws, use a small flathead screwdriver to press the release tab while pulling the wire out. Set the old outlet aside.
Connect the New GFCI Outlet
Before you install the new outlet, strip about half an inch of insulation from the end of each wire if the copper is damaged or corroded. The black wire connects to the brass screw (usually on the right side of the outlet when you are looking at it face-on). Wrap the bare copper end of the black wire clockwise around the brass screw and tighten it firmly — the wire should not slip when you tug it.
The white wire connects to the silver screw (usually on the left). Wrap it clockwise around the silver screw and tighten. The bare copper ground wire connects to the green screw (usually at the bottom). Wrap it clockwise and tighten. All three connections should be snug but not so tight that you strip the wire. If you are using the back-insert holes instead of screw terminals, strip the wire, insert it fully into the hole, and tighten the set screw next to it.
Install the Outlet and Test It
Carefully push the outlet back into the electrical box. The outlet should sit flush against the box with no wires pinched or folded underneath. Screw the top and bottom screws back in to hold the outlet to the box. Do not overtighten — the outlet should be snug but not warped. Attach the cover plate and screw it in.
Go back to your electrical panel and turn the breaker back on. Return to the outlet and press the test button on the face of the GFCI — it should trip when ready and cut power to the outlet. Then press the reset button to restore power. If both buttons work, the outlet is installed correctly. If the test button does nothing, turn the breaker off again, check your wire connections, and try once more.
When a GFCI Outlet Protects Multiple Outlets
Some GFCI outlets are wired to protect other standard outlets downstream on the same circuit. If you are replacing a GFCI that was protecting other outlets, you have two choices: install a new GFCI in the same spot (which will continue to protect those outlets), or install a standard outlet and move the GFCI protection to the breaker itself by replacing the breaker with a GFCI breaker at the panel.
If you choose to keep the GFCI outlet in place, the wiring is the same as described above. If you want to move protection to the breaker, you will need to hire an electrician — breaker replacement requires working inside the main panel, which is not a DIY task. Most homeowners keep the GFCI outlet where it is because it is simpler and allows you to test and reset protection at the outlet itself.
Common Mistakes That Cause Problems
The most common error is connecting the wires to the wrong screws. Black always goes to brass, white always goes to silver, and bare copper always goes to green. If you reverse hot and neutral, the outlet will not work safely. The second mistake is not stripping enough insulation — the bare copper needs to wrap around the screw, not the plastic coating. If plastic touches the screw, the connection will fail.
A third mistake is forgetting to turn the breaker back on after installation. If you test the outlet and nothing happens, check the breaker first before assuming the outlet is bad. Finally, do not reuse the old outlet if it is damaged, burned, or cracked. A damaged outlet can cause a fire. Buy a new one.
Tools and Materials You Will Need
A Phillips head screwdriver fits the outlet screws. A flathead screwdriver helps with the wire terminal screws and the release tabs on back-insert outlets. A voltage tester (also called a non-contact tester) costs $10 to $20 and is the safest way to confirm power is off. Wire strippers remove insulation if needed. A new GFCI outlet costs $10 to $25 depending on the brand and whether it has USB ports or other features.
You do not need a multimeter, a fish tape, or any other specialized tool. If you do not own a voltage tester, borrow one or buy one — it is the only tool that matters for safety. Do not skip this step and assume the breaker did its job.
Frequently Asked Questions
What if the outlet has two sets of screws on the back?
Some outlets have both screw terminals and back-insert holes. Use the screw terminals — they make a more reliable connection. Wrap the wire clockwise around the screw and tighten firmly. Back-insert holes are faster but more prone to loose connections over time.
Can I replace a GFCI outlet with a regular outlet?
Not in bathrooms, kitchens, garages, or within 6 feet of a sink — code requires GFCI protection in these areas. You can use a regular outlet if you install a GFCI breaker at the panel instead, but most people find it easier to keep the GFCI outlet at the location where it is needed.
Why does my new GFCI outlet keep tripping?
A new GFCI that trips constantly usually means there is a ground fault somewhere on that circuit — a wire touching water, a damaged appliance, or a short in another outlet downstream. Unplug everything on that circuit and press reset. If it holds, plug items back in one at a time to find the culprit. If it trips when ready even with nothing plugged in, the outlet itself may be defective.
Do I need a permit to replace an outlet?
Most jurisdictions do not require a permit for outlet replacement, only for new circuits or major rewiring. Check your local building department to be sure. If you are unsure about the wiring or uncomfortable working with electricity, hire a licensed electrician — the cost is usually $100 to $200 for a single outlet.
What is the difference between a GFCI outlet and a GFCI breaker?
A GFCI outlet protects only that outlet and any outlets wired downstream from it. A GFCI breaker protects the entire circuit. Outlets are cheaper and easier to replace, while breakers protect more outlets but require panel access. Most homes use GFCI outlets in bathrooms and kitchens and standard breakers elsewhere.