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Do Extension Cords Use Electricity When Plugged in?

Written by Edwin Jones / Fact checked by Andrew Wright

do extension cords use electricity when plugged in

We all know that cables are excellent for delivering electricity to any connected device. But have you ever asked, “do extension cords use electricity when plugged in without any connected device”?

Most of the time, the answer is no. However, there are some exceptions when it may utilize relatively little electricity. This may not significantly impact your utility bill, but it may have a negative effect in other ways.

Does Utility Extension Cord Use Electricity When Nothing is Plugged in?


In general, electricity is used by leaving things plugged in. Extension cords transmit the current for connected devices in an area with no nearby outlet. An example of this is when you use power tools in your workshop.

Most of the time, the cable itself does not use electricity. This means that if nothing is plugged into it, nothing will consume power. However, an electric cord uses energy depending on its internal component.

Read below for more details.

1. Extension Cord with Surge Protector

This type, often known as an energy saving extension cord, is common indoors. It offers surge protection features that safeguard your electronics from potential harmful faults. Its feature immediately activates when it detects overloads or risky electrical supply changes.

These cords essentially consist of a switch that allows you to turn the electrical connection on and off. Moreover, some of them have individual controls with lights for each outlet, making it easier to manage each appliance.

Due to its protection and lighting function, it may consume electricity.

2. Extension Cord with Power Indicator


Another type of extension cord that may use energy is one with a power indicator. When you plug in this electric plug extension cable, a light turns on, signaling that energy is flowing through it.

This way, you can be aware that the cord is energized, and it also brings you convenience when plugging your equipment in a dark room.

Note: Even though these types of extension cords use electricity, the current draw is very low. It amounts up to 0.036 kWh per month or less than 1 cent. Also, if you are looking forward to buying a new cord, these extension cables are highly recommended for safety assurance.

Frequently Asked Questions


Can You Leave an Extension Cord Plugged in Without Anything Plugged into It?

Extension cords are good for temporary purposes only and should not be used as a permanent circuit. Leaving your extension cord plugged in is not a good idea, since it may pose a tripping hazard, especially in busy areas of the home like living rooms or kitchens. Therefore, you should always store your cords properly when not in use.

What Happens if You Leave an Extension Cord Plugged In?

Nothing will happen if you leave the cord in a socket without appliances. However, it does not mean that it is safe to leave extension cords plugged in. If water comes into contact with the connection, electrical shocks can happen.

Does Leaving a Charger Plugged In Use Electricity?

Depending on the type of charger, leaving an extension cord plugged in uses electricity. Modern chargers have a smart feature that automatically stops their function when nothing needs to be charged. These devices do not use any electricity.

However, some models, especially older ones, might not have said feature. As a result, they may use some energy.

Does Plugging an Appliance into an Extension Cord Waste Energy?

The appliance’s rating and cord size determine the answer. If the cable is small and the appliance uses a lot of power, energy wastage is more likely. This is because the electricity may convert to resistance and cause the cord to overheat.


Leaving extension cords plugged in is something many homeowners do. The energy consumption is quite minimal here, but when it comes to safety, it could lead to a serious incident if your circuit is faulty.

I hope this article clarifies your question: “Do extension cords use electricity when plugged in?” Also, always remember to unplug any cables that are not in use. This will keep them in good shape, potentially extending their lifespan and safety.

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