If You See Burn Marks on Plug Prongs, Here’s What to Do

They’re a sure sign that something is overheating

Man plugging phone charger into electrical outlet
Photo: Maskot / Maskot / Getty Images
Man plugging phone charger into electrical outlet
Photo: Maskot / Maskot / Getty Images
Kat Brancato
Written by Kat Brancato
Contributing Writer
Updated December 18, 2023

Highlights

  • Burn marks on plug prongs can be caused by faulty wiring. 

  • Corrosion inside an outlet can also cause burn marks on plug prongs.

  • It’s dangerous to use a plug that has burn marks.

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You just grabbed your go-to phone charger or went to plug in your vacuum cleaner when you noticed scorch marks on the plug prongs. Should you be concerned? No matter what type of appliance or device it is, if you ever see burn marks on plug prongs, it's a red flag and should be addressed immediately. 

It’s best to hire a professional electrician near you to determine the root of the problem and fix any electrical issues in your home. In the meantime, never plug something in that has burn marks, as this could cause a fire or other serious problems. Below, we break down the common causes of burn marks on plug prongs and the next steps to take.

1. Loose Connections

One of the most common reasons for burn marks on plug prongs is arcing from loose connections. When wires in the outlet become loose and touch areas they aren't supposed to, it can cause arcing and overheating, which will also cause damage to the plug. 

Arcing is a serious issue and a major cause of house fires. Check the outlet for signs of scorching or discoloration. If you see anything, call a professional electrician right away. 

2. Circuit Overload

Too many appliances plugged into an electrical outlet
Photo: Raimund Koch / The Image Bank / Getty Images

A circuit overload can also cause burn marks on plug prongs. A few things can cause a circuit to overload, such as too many high-voltage appliances plugged into an outlet, a device that requires more electricity than the circuit's capacity, or even a faulty appliance. Older homes may have out-of-date electrical systems and are more susceptible to overloading circuits. 

When a circuit overloads, the wiring gets too hot. This can damage the insulation around the wires and even melt the outlet. 

If you notice sparks when you plug in a device, smell burning plastic, or see burn marks on the outlet, you should have a professional electrician inspect and fix the issue immediately. Never plug other devices into an outlet that shows these signs.

3. Faulty Wiring

If a plug or outlet feels hot to the touch, one of the most common reasons is faulty wiring. Improper wire installation, incorrect wire sizes, and worn-out wires are some examples of faulty wiring that can cause burn marks on plug prongs and outlets. 

Faulty wiring is extremely hazardous, which is another reason why it's always a good idea to seek the assistance of an experienced electrician to fix the issue.

4. Corrosion 

Outlets that have corrosion can cause burn marks on plug prongs as well. Exposure to moisture or water can cause rust and corrosion in the outlet; dust and debris can also cause corrosion.

As it builds up, corrosion will cause electrical resistance and make the outlet overheat. It can also cause arcing, which can lead to a short circuit in the outlet. 

To protect against fires, you should replace an outlet immediately if it has corrosion. If you have electrical experience, you may be able to do it yourself, but working with electricity can be dangerous, so leave it to the professionals if there’s any doubt.

5. Damaged Plug

Hand plugging in power cord into electrical outlet
Photo: tab1962 / iStock / Getty Images Plus / Getty Images

Sometimes, it’s the plug itself that’s damaged, which can cause a poor connection between the outlet and the plug. This results in an electrical arc and causes burn marks on plug prongs. Inspect the plug itself to see if the prongs are loose, bent, or damaged. 

Also, check for cracks or wires showing. If there is any damage to the plug, then you should not use it. Have the plug repaired or get a new appliance instead. 

Frequently Asked Questions

You should never use a plug with burn marks because it can cause a fire or even an electrical shock. The burn marks could be caused by a dangerous underlying electrical problem, so it’s important to call a qualified electrician right away. 

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Learn more about our contributor
Kat Brancato
Written by Kat Brancato
Contributing Writer
Kat has spent over 10 years sharing her knowledge on home ownership, finance, and inexpensive ways to do things yourself. Her work can be found in publications like Better Homes & Gardens and Real Simple where she writes tips on organizing, cleaning, gardening.
Kat has spent over 10 years sharing her knowledge on home ownership, finance, and inexpensive ways to do things yourself. Her work can be found in publications like Better Homes & Gardens and Real Simple where she writes tips on organizing, cleaning, gardening.
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