How Electricians Replace a Two-Prong Outlet with a Three-Prong Outlet

person attaching wires to a GFCI outlet on a white tiled wall

If you live an older home with two-prong outlets, you’re probably starting to run out of outlet space. Even worse, you probably haven’t been able to make use of your devices that require a three-prong outlet.

Fortunately, you don’t have to settle for an overabundance of the wrong type of outlet. You can hire a professional electrician to change out some of your outdated outlets for a more modern three-pronged design.

Here you’ll learn how outlet replacement works and what an electrician must consider:

The Three-Prong Access vs. Affordable Solution Conundrum

There are abundant reasons homeowners shy away from rewiring their homes. Although this option offers the safest solution for three-prong outlet access, it may not be the most feasible one.

Rewiring a home is expensive and time-consuming. Thankfully, there are other ways your electrician can upgrade your outlets without rewiring. For example, ungrounded three-prong outlets can be installed. However, there are risks involved with using three-prong outlets that aren’t grounded.

Two-prong outlets have no ground wire, without which the risk of electrocution and appliance damage is substantial. Simply adding an outlet with an additional prong will give you added appliance access, but it will not give you the safety that grounding provides.

Should You Change a Two-Prong to a Three-Prong Outlet with No Ground Wire?

Converting a two-prong outlet to an ungrounded three-prong GFCI protects you from electric shock. However, an ungrounded three-prong GFCI will not provide the necessary ground protection that prevents sensitive electronics from being fried during voltage fluctuations.

Think using a surge protector strip will fix the problem? Unfortunately, those devices are only as good as the outlet they’re connected to. No grounded outlet = no surge protection.

We do not recommend installing ungrounded three-prong outlets, but we understand that it can provide a temporary, cost-effective solution for some homeowners.

How Electricians Replace a Two-Prong Outlet with a Three-Prong GFCI

Here’s how professional electricians replace two-prong outlets with three-prong GFCI plugs without running a new ground wire to the electrical panel:

  1. We turn off the power to the outlet using the service panel. This is then confirmed at the outlet with a multimeter.
  2. We remove the plate screw and cover, as well as the two screws holding the old receptacle into the box.
  3. We pull out the old outlet box without cracking the wiring. Then we gently extend it to gain access to the wires.
  4. We disconnect the old outlet.
  5. Some old boxes are tight, so the new GFCI must be test-fitted by gently pushing the wires back and ensuring the new box will fit. If it doesn’t fit, a new, larger electrical box will be used.
  6. If the wires aren’t long enough, we add 4-6" extension (“pigtails”) using the appropriate wire for the circuit amperage: 15 amp = 14 gauge; 20 amp = 12 gauge. (DIYers with significant electrical experience attempting this project would have to pick up one white wire and one black wire from a local hardware store, along with the appropriate wire nuts to add the extensions.)
  7. If the wires are long enough, the electrician will look at the terminals on the GFCI and identify the “Line” terminals. These are the only ones that will be used. The wires will be connected:
    • Black wire to the brass “Line” terminal screw.
    • White wire to the silver “Line” terminal screw.
  8. We gently fold the wires back into the box, pressing in the new outlet.
  9. We screw the box back into its original location.
  10. We then test the outlet by pushing RESET to turn it on, and then TEST to shut it off. We’ll reattach the plate and apply a NO GROUND sticker.

How to Ground a Two-Prong Outlet

To ensure safety, eventually you’ll want to have grounded outlets. If your home is grounded but some of your outlets are not, bringing in a licensed electrician is the best way to ensure the modifications are completed safely and correctly.

Grounding an outlet requires attaching a wire and running it all the way from your outlet to the grounding screw at the back of your electrical box, which is often a long, complicated endeavor, and exceedingly painful for the inexperienced — sometimes “shockingly” so. Because of this, you should make sure to give an electrician a call, rather than risk the pain of doing it on your own.

electrician replacing an outlet

Trust Mr. Electric to Upgrade Your Two-Prong Outlets to Three-Prong

Mr. Electric® is here to help you avoid unnecessary safety risks. Contact us today to upgrade your two-prong outlets to three-prong outlets safely and quickly. You can click the button below or call us at (844) 866-1367 to connect with your local Mr. Electric.

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This blog is made available by Mr. Electric for educational purposes only to give the reader general information and a general understanding on the specific subject above. The blog should not be used as a substitute for a licensed electrical professional in your state or region. Check with city and state laws before performing any household project.