Do GFCI Outlets Work Without a Ground Wire?

Allie Ogletree
Written by Allie Ogletree
Updated March 24, 2022
Close-up of a GFCI outlet
Photo: The Toidi / Adobe Stock

Highlights

  • GFCI outlets work without grounding but are less safe than grounded.

  • It costs around $210 on average to replace old outlets with GFCI ones.

  • GFCI outlets offer more protection than ungrounded, traditional outlets. 

  • Always have a professional electrician install the GFCI outlets.

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When most people flick the switch on in their kitchen or plug in holiday lights outside, they expect immediate light. But if your home is ungrounded and lacks GFCI outlets, your wants may be clouded by a fear of electrical shock. Here’s what you need to know about GFCI outlets and if they can keep you safe without a ground wire.

What Is a GFCI Outlet?

A ground fault circuit interrupter (GFCI) is a circuit breaker designed to prevent electrical faults in and around your home. GFCI outlets work by monitoring how much electrical current flows to and from your electrical appliances and products. If the GFCI monitoring system detects a difference between the current that exceeds five milliamperes, it will trip the power, potentially saving you from electrocution. 

Ground Faults Are Dangerous

There’s a reason lightning strikes the ground; electricity always flows to the earth because it has a negative charge, while the ground has a positive charge. When something goes awry with the conducting connection between the conductor and the conducting recipient, that electricity will race through whatever source it can to reach the ground. 

In short, if you’re the nearest pathway to the ground, it will shock you. That’s where GFCI outlets come in to interfere with that possibility, helping to keep you safe.

Ungrounded Outlet vs. Grounded Outlet

You can identify an ungrounded outlet by its two-prong design, and you’ll usually find them in older homes. These outlets don’t have a grounding path to allow electrical surges to travel down to the ground rather than your devices or body. As such, they’re not nearly as safe as a grounded outlet.

Keep in mind that some three-prong outlets are also ungrounded. Ungrounded three-prong outlets are installed using only two wires, just like a two-prong outlet. However, that third prong—which is designed for grounding—isn’t in use, making the outlet as much of a safety hazard as a two-prong outlet. 

The only ways to know if a three-prong outlet is grounded are to use a receptacle testing device or have a local licensed electrician take a look at the receptor to see if it has three wires.

Can a GFCI Outlet Be Installed Without a Ground Wire?

Close-up of a GFCI outlet
Photo: Lost_in_the_Midwest / Adobe Stock

Now for the big question: can you install a GFCI outlet with no ground wire? In short, yes. If your circuit doesn’t have a ground wire, you can still install a GFCI outlet for protection. GFCI outlets without a ground wire are legal and work; however, choosing to install GFCI outlets without a ground wire does come with some disadvantages. 

Ungrounded GFCI Outlets Offer Less Protection

For one, though ungrounded GFCI outlets offer you some protection (the GFCI outlet will sense when there is a ground fault and shut off), they will not protect your electronics in the chance of a ground fault. You need a ground wire and surge protector for the most protection against damaged electronics.

Plug-In Testers Are Less Reliable with Ungrounded GFCI Outlets

Another problem with installing a GFCI outlet without a ground wire is that a plug-in tester on the GFCI outlet won’t work, even if pressing the actual test button on the receptacle does. This can be confusing, but if the receptacle trips via the built-in tester, this indicates that it works. 

Homeowners Must Maintain Identifying Labels

You also have to label the face of all ungrounded GFCI receptacles with “No Equipment Ground” and “GFCI Protected” stickers, which either come included in the GFCI packaging or purchased at a hardware store. 

Does Replacing Ungrounded Outlets with GFCI Outlets Make Them Grounded and Safe?

Just because you replace an underground outlet with a GFIC outlet doesn’t mean it’s grounded. However, you can replace ungrounded outlets with GFCI outlets, and it does make the outlet safer than if you didn’t have one installed. 

So, if you’re concerned about the safety of electrical outlets in your home—especially ones within six feet of water sources—it’s a good idea to install GFCI outlets.

Identifying GFCI Outlets in the Home

GFCI outlets are extremely important for keeping you and your family safe from electrical shocks, but they can be hard to spot. Here’s how you can identify GFCI outlets:

  1. Look for the “Test and Reset” GFCI outlet button

  2. Check for a small LED light 

  3. Open your circuit breaker box and check for “push here to test” buttons

Circuits with a push test button indicate that all outlets within that circuit breaker have GFCIs installed.

Checking Your GFCI Outlets

Those test buttons aren’t just for show—though it’s very easy to ignore them as we go about our daily routines! Though GFCI outlets have a lifespan of around 15 years, they can and sometimes do stop functioning well before then. So, once you’ve identified all of the outlets in your home, it’s a good idea to check them every month to make sure they still work. 

Where to Install GFCI Outlets

Knowing where to install different types of GFCI outlets can be lifesaving. GFCI outlets are best installed in places susceptible to electrocution, such as:

  • Kitchens

  • Bathrooms

  • Outdoor areas

  • Laundry rooms 

  • Basements 

  • Garages

  • New homes near water, and more 

However, these outlets aren’t just limited to areas of the house that pose the most safety risks. You can install GFCI outlets in most outlets in your home if you’re concerned about electrocution. A general rule of thumb is that any outlets within a six-foot radius of a water source should have one of these outlets installed.

In fact, the National Electrical Code (NEC) requires these locations—and anywhere else that is prone to dampness—to have GFCI outlets installed. This is an update from previous regulations, which had finished basements exempt from needing GFCI outlets; now, all basements require GFCI outlets.

How Much Does It Cost to Install GFCI Outlets?

A GFCI outlet costs between $130 to $300 per receptacle, or an average of $210, including labor. Each GFCI outlet costs anywhere from $7 to $25 apiece, so most project costs go to labor. Outdoor installations cost more, so add around $15 per outlet to the total project cost.

Can You DIY a GFCI Outlet Installation without a Ground Wire?

GFCIs are relatively easy to replace because they’re integrated into the actual outlet, but, as with any electrical project, there’s always a risk of getting shocked. If electrical safety isn’t your strong suit, it’s a good idea to call in a pro. This is especially true if you’re planning on installing the outlets without a ground wire. 

GFCI outlets contain multiple wires that are not interchangeable, meaning you have to know which wire goes where and avoid connecting the ground terminal. Unless you’re an electrician, it can be tricky to tell the difference and label the wires accordingly. Doing it incorrectly can result in a code violation.

Calling in the GFCI Pros

To avoid potential electrocution and code violations, consider hiring a pro. An electrical company near you can install all of the GFCI outlets in your home, identify areas of your home where you might be legally required to have one installed, and conduct tests to ensure that the ones already installed in your home are functioning correctly. 

This leads us to our last point—GFCI outlets can and do stop working over time, so it’s a good idea to have them checked regularly and replaced as needed.

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