How to Replace the Plug on a Lamp

Stripping the Old Lamp Plug and Cord

Unplug the lamp from the electrical outlet. Turn off the lamp at the switch for added protection against electrical shock. Grab the base of the plug and pull it straight out from the wall outlet. Avoid touching the prongs since they may still have a small charge left in them. Never cut a cord while it’s still plugged in, or else you could get seriously injured from electrical shock. If there’s damage on the power cord near the plug, wear rubber insulated gloves so you don’t have to touch any exposed wires.

Cut the old plug and 1–2 in (2.5–5.1 cm) of the cord with a utility knife. To start the process of replacing the plug, measure 1–2 inches (2.5–5.1 cm) down from the plug and carefully slice through the cord with a utility knife. Make the cut as straight as possible so you’re less likely to fray the wires. Throw away the old plug as soon as you cut it off. If you have trouble cutting the cord with a utility knife, try using a pair of scissors instead.Tip: If there are cracks, holes, or frays anywhere else on the cord, remove the damaged section as well.

Separate the wires on the last 1 in (2.5 cm) of the cord. Look for the thinner section of insulation running through the middle of the lamp cord. Make a ⁄2 in (1.3 cm) cut in the middle of the cord, making sure you don’t damage any of the internal wires. Hold onto the each side of the cord and gently pull it apart until you separate 1 inch (2.5 cm). If your lamp cord doesn’t have a thin piece of insulation running down the middle, carefully slice through the cord’s insulation to expose 1 inch (2.5 cm) of the wires inside of it.

Remove ⁄2 in (1.3 cm) of insulation off of each wire with wire strippers. Grip one of the wires in the jaws on a pair of wire strippers so it’s ⁄2 inch (1.3 cm) from the end. Squeeze the handles together to clamp down on the insulation and pull the strippers toward the end of the cord. Throw away the piece of insulation that comes off of the wire. Repeat the process on the other wire so they’re both exposed. If your lamp has a third wire for a grounding port, strip it as well.

Twist the frayed ends of the exposed wires so they’re easier to attach. Grip the exposed end on one of the wires and squeeze together any frayed ends. Rotate them clockwise so they form into a solid wire that doesn’t fray. Repeat the process for the other wire on the power cord. Don’t twist the 2 wires together since you won’t be able to attach them to the plug.

Wiring the New Lamp Plug

Get a polarized replacement plug for your lamp. Opt for a replacement plug that has 1 prong that’s wider than the other since it provides the most protection against electrical overload. Avoid using non-polarized plugs, or plugs where the prongs have the same width, since they aren’t up to electrical code. Choose a plug that has a similar color to the lamp’s power cord so it doesn’t clash. You can buy polarized replacement plugs from your local hardware store. If your original lamp plug had a grounding prong, make sure you buy a replacement plug with one as well. Make sure to buy a new plug in the same style and model as the last one.

Unscrew the back cover from the replacement plug. Use a screwdriver to remove the screws holding the replacement plug together. Pull the plastic cover off of the plug to separate it from the section that contains the prongs and screws. Set the screws aside while you’re working so you don’t misplace them. Some replacement plugs have a hinge rather than a cover. Remove the screw holding the plug together and pull the sides apart to open the hinge.

Slide the cover onto the lamp’s cord. Hold the 2 wires from the lamp together so they’re able to fit through the back hole of the cover. Push the cover onto the wires and pull them through to the other side. Keep the cover about 3–4 inches (7.6–10.2 cm) from the end of the cord while you work so it doesn’t get in the way. If the replacement plug you’re using has a hinge instead of a separate cover, you may skip this step.

Secure the wire with ribbed insulation to the plug’s silver neutral screw. Look at the insulation on each wire and find the one that has the ribbed edges, which means it's the neutral wire. Bend the wire into a small hook and put it underneath the silver screw on the replacement plug’s prongs so the wire goes around it clockwise. Tighten the screw with your screwdriver so it firmly presses against the wires. The silver screw connects to the wider prong on a polarized plug, which is the neutral or negative side. If your lamp has 3 wires, then the neutral wire may have white insulation rather than having a ribbed texture.Variation: If neither of the wires has ribbed insulation, then it doesn’t matter which one you attach to the screw.

Hook the wire with the smooth insulation on the plug’s brass screw. Locate the wire that has smooth edges along the sides of the insulation, and bend the exposed end into a hook. Put the wire underneath the brass screw on the side of the replacement plug so it wraps around the screw clockwise. Tighten the screw with your screwdriver so the wire has a firm connection. The brass screw connects to the smaller prong, which is the “hot” or positive side. If your lamp has 3 wires, then use the wire that has red or black insulation.

Attach the ground wire to the green screw, if your lamp has one. Look for the green wire from the lamp cord and bend a small hook shape on the exposed end. Locate the green screw on the replacement plug and tuck the wire underneath it. Tighten the screw so the wire doesn’t come loose. Most household lamps don’t have a ground wire, but they may if they are industrial-strength lights or use high-wattage bulbs.

Screw the plug back onto the cover to hide the wires. Slide the plastic cover back over the ends of the wires and hold it against the prongs. Check the cord to make sure none of the exposed wires stick out from the back of the plug. Place the screws back in the holes and turn them clockwise to tighten them. If you’re using a hinged replacement plug, then guide the cords into the hole at the back of the plug before snapping it closed. Tighten the screw on the plug so it stays closed.

Plug in your lamp to test if it turns on. Use an outlet that you know works so you know there aren’t any other electrical problems preventing the lamp from turning on. Plug the lamp into the outlet and switch it on to see if it lights up. If it works, then put the lamp back on its original outlet. If the lamp still doesn’t work, take apart the plug and check that you connected the wires to the correct screws. Switch them if you need to before trying the lamp again. If it still doesn’t work, then there may be a problem with the lamp’s bulb socket instead.