2 min read
close up of electrical wires bellvue co

What Common Electrical Wire Colors Mean

Knowing the electrical wire color codes is crucial for anyone tackling small electrical issues. If you’re having trouble fixing electrical problems on your own, it’s time to contact Prolectric.

Since the 1940s, all homes in the United States have used the same electrical cord wire colors. Knowing what these electrical wire colors mean is crucial for anyone attempting electrical repairs. Each color represents a different wire function and should be handled in a manner specific to that function. And of course, all electrical wires could be carrying current, so all precautions should be taken before attempting a repair. Calling a professional electrical contractor is always recommended instead of trying this dangerous, complicated work yourself.


There are several standard electrical wire colors that you can commonly find in your house. However, exceptions can always exist. Professional electrical contractors are trained to identify electrical systems safely. If you’re a homeowner, it’s smart to keep an electrical wire color coding chart with this information somewhere accessible in case of emergency measures. But if you have any doubt at all about your system, you should always call a licensed professional first.

Black Electrical Wires

With black wires, it’s safest to assume they are live always. Black marks a wire that sends power to your outlets and light switches. They’re also used as a connection to link switches to the electrical load. Remember, of all the common wire colors black wires are almost always hot.

Red Electrical Wires

Red wires are used in 220-volt circuits, the kind used for large appliances. You’ll see red wires in stoves, washers, and air conditioners. They are used as switch legs in circuits, connecting switches to power the same as black wires. But you may also see them in smoke detectors, where red wires connect your smoke detector to the house power. Red wires can be attached to either another red or black wire. Both red and black electrical wire colors should be approached as if they are hot.

Blue and Yellow Electrical Wires

Blue and yellow wires carry power, but they’re not standard for your electrical outlet wire colors. Instead, you’re more likely to see them in lights that are wired to correspond with light switches. This means you can see yellow in circuits from ceiling fans or hardwired ceiling lights. They can also be used in outlets that are connected to switches themselves.

Blue wires are typically found in three or four-way switches. For instance, if you have a light switch for your foyer inside the outer door, but you can also turn it off from another switch inside the interior door, that’s a three-way switch, and where you’ll typically run into the blue.

White and Gray Electrical Wires

Home electrical wire colors are designed to be intuitive, so it’s no surprise that the white and gray wires are meant to be neutral. This means they’re a safe return path for current carried by black wires, and they’re grounded to a neutral bus bar. The bus bar is a piece of metal within your home electrical panel that attracts any current to be safely distributed throughout your system instead of overloading or blowing a fuse. White and gray mean the same function and are interchangeable. But even though “neutral” may sound safer, these wires can still carry current, especially if something is wrong within your electrical system.


Knowing the electrical wire color codes and their meanings is helpful for anyone tackling small electrical work, such as installing a light. However, electrical work can be very dangerous, and should always be approached with caution. The electrical contractors at Prolectric have been serving the Bellvue, Wellington, and Fort Collins communities for over 30 years. When it comes to electrical installations, they can handle any job. Call today to get your free estimate.

Get in Touch With Us

At Prolectric Electrical Services, our electrical contractor is ready to provide you with the professional assistance you need. Schedule a service by calling (970) 222-4740 or filling out the contact form below.