24 Hour Emergency Services Available
(773) 378-9690 Request Service

Electrical 101: Wire Colors

March 10, 2021 | Blog

Did you know that the different colors of the wires have specific meanings? Yeah, that’s right, the wires aren’t colored just to look pretty. Each wire color indicates the wire’s purpose and job, which helps you to know how careful you should be when you’re handling them. It’s extremely important to know what these colors mean, especially if you’re trying to do some DIY electrical work. Electrical safety should be of one of the top priorities wherever you are, as it is one of the factors that could potentially cause a major problem. Better understanding means more safety, so here is a quick guide to electrical wire colors.


When you see a green wire, they should always be by themselves. The green wires are known as the grounding wires, which means it should never connect with any other color wire. By connecting to a grounding outlet box, these wires are more of a preventative measure. If another colored wire were to ever come into contact with metal or something else that is conductive and has the ability to carry electricity, the green wire is there to make sure it grounds out.


Black wires, like red wires, are considered hot and have an electric current flowing through them. Most commonly, the black wire is used for carrying the current from the power source to the outlet. If you think about the basic wires in your houses, most of them are black. These wires are never meant to be a grounding or neutral wire and is always being used to transfer power. Since it is never a neutral wire, make sure to always use extreme caution when dealing with a black wire, as it should be considered a live wire at all times.


Red wires, aka hot wires, are used as the secondary wire. Carrying 220-volt circuits, they can be just as dangerous as the black wires. They are commonly used when installing ceiling fans, smoke detectors and other lighting fixtures. Hot wires are the only wires that can connect with each other, so make sure to practice safe handling or call an electrician when you’re using red and black wires.

White and Gray

The gray and white wires are most commonly known as neutral wiring. Though that is their most common use, they can still carry a current. If a white wire is ever marked with black or red, it means that it is no longer neutral and is being used as a hot wire, so continue to use caution even though it’s still white wire. White wires are typically found in residential buildings while gray wires tend to be found more in commercial buildings. The white and gray wires can only be connected to one another.

Blue and Yellow

Blue and yellow wires are most commonly found in the conduits of commercial buildings. Typically found in more complex circuits, they are used to conduct the current between switches and poles, which then makes them known as travelers. The blue wire’s main purpose is to act as a traveler for three-way and four-way switches, while the yellow wires are used as switch legs to ceiling fans, light switches and other structural lighting areas. These wires are too complicated for outlet wiring for the common plug-in devices.

Other colored wires

The previous colors listed are just the most commonly used colors when it comes to electrical wiring. There are other colors and variations of colors used in wiring, but as long as you know the basics of the main seven colors and practice safe handling with all of them, you have nothing to worry about.

The most important thing for you to remember when dealing with wiring is safety first. Though they are just small, simple little wires, they can cause a lot of damage. It is extremely important to know the difference in the colors of the wires and handle them with the proper care, especially when doing it on your own. If you don’t feel comfortable handling the wires yourself, contact Arnold Electric Services to assist you with your electrical needs.

Why Choose Arnold Electric?

Reliable Service
We believe in providing premium electrical services, all backed by our 5 year parts and labor warranty
Upfront Flat Rate Pricing
Emergency calls and regular service calls are performed on a flat rate. No surprises!
Quality Products
Safety is our mission. We only purchase the highest quality materials from trusted suppliers.

What Our Clients Say

Fantastic Service

I have used Arnold Electric a few times for my business. I wasn’t sure what my options were for lighting in my office. Jack was so nice to bring some samples for me to try before installing! They are wonderful!

Dr. Lauren Shultz

Reliable and Professional

The team over at Arnold Electric has been great to work with. We recently purchased a home and have had Pedro out to do a review of the electrical system, make some minor repairs and present some options to improve the out dated and DIY wiring in our home. The team has done a great job of communicating expectations and explaining everything for us.

Kirk Heavner

Excellent Work

Very easy to work with, excellent work on jobs big (new underground line to a detached garage) and small (changing the interior fixture.

Lauren Harms

Punctual, Courteous and Clean

This company is absolutely the most professional and conscientious electrical contractor I’ve ever had the pleasure of hiring. I’ve used them several times from things like replacing my electrical panel, to wiring issues, to installing a ceiling fan. I will also use them for anything else electrical going forward. They’re always punctual, courteous and clean. I’m very particular, and hard to please. I’m not afraid to call and complain about less than perfect service from anyone I hire. Arnold Electrical Service, thank you for all the jobs well done!

Jesse Mills

Highly Recommend

My husband and I highly recommend Arnold Electric. Jack Arnold is the owner and is very detailed and professional. Follow Arnold Electric on Facebook and get some great tips and information along with current job details.

Debbie Neer

Fair Pricing and Excellent Work

Jack’s team came in and did a complete home inspection and repaired a light above my wife’s sink. My marriage has been saved now that the light is fixed. Very fair pricing and excellent work!

Douglas Sheehan

Reasonable Price & Professional

Joe came to my house to fix a dumb thing I did. (DON’T DO YOUR OWN ELECTRICAL WORK!) He was friendly, fast and very helpful, answering all my questions in a polite and tolerant manner.
The charges were very reasonable for the professional quality service I received. They will be coming back to do some new wiring and circuits soon. Highly Recommend!

John Buckley