How to Safely Replace Two-Prong Outlets


Replacing outdated two-prong outlets with modern three-prong outlets is an important electrical upgrade to make your home safer. Two-prong outlets do not have a ground wire, which means your devices and appliances are at risk of shocks and damage. Upgrading to three-prong outlets adds a ground wire for protection.

However, removing those old two-prong outlets and installing new ones requires working with home electrical systems. Without proper precautions, you risk electric shocks, fires, and damage. This guide covers everything you need to know to safely replace two-prong outlets yourself.

Dangers of Two-Prong Outlets

Two-prong outlets have only two slots to insert plugs, providing a hot and neutral wire. They lack a ground wire and grounding hole. This missing ground exposes you and your devices to risks:

Replacing two-prong outlets eliminates these serious risks by providing essential grounding.

When a Professional Electrician is Needed

While replacing an outlet is within the DIY capabilities of many homeowners, there are some situations where you should call a licensed electrician:

When in doubt, contact a professional. Installing ground fault circuit interrupters (GFCIs) also often requires an electrician's expertise.

How to Replace a Two-Prong Outlet

Replacing a two-prong outlet with a three-prong outlet involves five main steps. With proper precautions, a homeowner can safely perform this upgrade DIY.

Step 1: Turn Off Power and Test

Shut off the circuit breaker for the outlet you want to replace. The outlet should be on its own dedicated circuit. Test that the power is off by plugging in a lamp or outlet tester. Confirm the outlet is dead before touching any wires.

Step 2: Remove the Old Outlet

Use a screwdriver to detach the cover plate screws and outlet mounting screws. Carefully pull the old outlet out of the electrical box without touching any wires. Watch for backstab connections that release as you remove it.

Step 3: Disconnect Wires

With the outlet out, disconnect the hot/live (black), neutral (white), and any ground (green/bare copper) wires. Note where each wire was connected. Remove any wire nuts and backstab connections.

Step 4: Prepare the New Outlet

Strip 3/4 in. insulation from the ends of each wire if needed. Connect the wires to the new three-prong outlet following wiring diagrams, matching hot, neutral, and ground wires to the corresponding outlet terminals. Secure the connections by tightening the screws or inserting wires into the push-in holes.

Step 5: Mount and Test the Outlet

Carefully sit the new outlet inside the electrical box without pinching or twisting wires. Secure it with long screws through the mounting ears. Attach the cover plate, turn the circuit breaker back on, and test that the new three-prong outlet works.

Wiring a Three-Prong Outlet

Follow these best practices when connecting wires during outlet replacements:

Observe all electrical codes for safe and legal outlet wiring.

Creating a Ground Connection

To complete the grounding circuit, the new outlet also needs a ground wire attached to the grounding electrode system. This involves:


Never connect the ground wire to neutral or use neutral as an improvised ground on three-prong outlets! This defeats the outlet's grounding and protection.

GFCI Outlets vs. Three-Prong

While ground fault circuit interrupters (GFCIs) can provide protection on circuits with no ground wire, upgrading to true three-prong grounded outlets is better:

When possible, replace two-prong outlets with properly grounded three-prong outlets for maximum protection and compatibility. Only use GFCIs as a secondary option if grounding isn't feasible.

Safety Tips for Outlet Replacement

Take these precautions whenever replacing old two-prong outlets to ensure you stay safe:

Follow these basic safety rules, take your time, and be cautious when dealing with electrical systems. That will keep you safe during your upgrade to modern three-prong outlets.

Summary of Replacing Two-Prong Outlets

Upgrading old two-prong outlets to properly grounded three-prong outlets makes your home's electrical system safer:

Replacing those outdated two-prong outlets provides peace of mind knowing your home's electrical system is safer. Carefully following the steps in this guide allows you to upgrade to modern three-prong outlets yourself.