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How to Splice an Extension Cord? – Only 3 Simple Steps

Written by Edwin Jones / Fact checked by Andrew Wright

how to splice an extension cord

When you cut your extension cord by mistake, you may be inclined to replace it straight away. There’s nothing wrong with that, especially if you have enough money.

However, thinking of repairing your damaged cable is a wise decision, especially if it is still in good condition aside from being cut.

Now, if you want to know how to splice an extension cord, I have prepared a guide below that is easy to follow.

Step-By-Step to Splice an Extension Cord


Utilizing extension cord connectors is good for the connection between your device and outlet. But they can’t protect the entire length of the cord, which can easily get damaged.

When wrapping extension cord, you may notice some visible cracks on it caused by animal bites or contact against sharp objects.

In such cases, you do not need to replace it immediately. Instead, just repair the extension cord so you can use it again.

The repair process is very simple, consisting of connecting the extension cord wiring. However, you should do it properly to eliminate the risk of electrocution.

If you want to fix a cut extension cord, here are the tools and guide you can follow.

What To Prepare:

Here is the extension cord splice kit you must have to connect the wires adequately.

Step 1. Remove the Insulation Cover and Strip the Wires

  • The first thing you need to do is to snip off the ends of the damaged wire to make it nice and clean.
  • Now, remove the outer insulation of the cord (around 5cm of it).
  • Then, using your utility knife, carefully cut 1-inch off the internal insulation jacket to access the wires inside.
  • After removing the jacket, you will see three pieces of wire, primarily green, black, and white. Next, using your wire stripper, strip all the ends of the wire.

Do this to both ends of your cut extension cord.

Step 2. Connect the Wires

  • You can insert the heat-shrink tube on one side of your cord to test its size. Ensure that the tube fits the intended connected ends of the cable perfectly after shrinking to make a waterproof finish.
  • Now, for connecting the wires, you can connect those with the same color. Twist the exposed parts of the wires together.
  • Next, you can start soldering the connection. Clean the tip of your soldering iron. Then, apply some flux to the wire, and melt the solder on the wire.

This exact process will do for other cable strands.

Step 3. Seal the Wire

After connecting the wires, you must seal them to create a waterproof extension cord splice.

Electrical liquid tape may be the best option for achieving a secure seal for the wire. However, using it may cause a mess on your work surface, so you should cover your table with paper.

  • Stir the sealant thoroughly before applying the first coating to each connected wire. Inspect the wire to verify you haven’t missed any areas.
  • Wait 10 minutes for the coating to dry before applying another coat.
  • During the second coating, apply sealant along the edges where the outer jacket is removed.
  • Then, wait at least four hours for the liquid tape to dry based on its instructions.
  • Finally, put the heat-shrink tube over the connected wires and heat-blow it.



Can You Repair a Broken Extension Cord?

Yes! You can repair a damaged extension cord as long as its wires are usable. You can try the method above for mending a cut power cord.

Alternatively, if your extension cable damage is on the plug part, you can splice plug and replace it with a new part.

But if your problem is a melted extension cord, I’m afraid you need a whole new one.

How Do You Repair an Extension Cord that has Been Cut?

Splicing extension cords is a quick way to repair a cord that has been cut. It can be done by simply connecting the wires and insulating them.

Is it Safe to Splice a Power Cord?

The NEC says we should not splice an electrical cord.

However, based on my experience, it is something I can do when I’m in a pinch and cannot find an intact cable. My splice power cord has never caused me problems.


Knowing how to splice an extension cord will allow you to save some money by not buying a new one. However, to keep the quality of the cord, you need to consider using the method and material we described above.

That said, if you have enough budget to purchase a new cable, it is the best thing to do as nothing beats the quality of a new product.

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