ELECTRICAL WIRING COLOR CODES - CONTENTS: Electrical Wiring Color Codes & Conventions for 120V or 240V A/C Circuits in Buildings
- Tables of Electrical wiring color code conventions for 120V & 240V AC circuits in buildings in the U.S., Canada, the U.K. & the I.E.C. Included is a chart of wiring color code abbreviations.
InspectAPedia tolerates no conflicts of interest. We have no relationship with advertisers, products, or services discussed at this website.
Electrical wiring colour codes:
This article describes the electrical wiring color code conventions for 120V or 240V AC circuit wiring in buildings in Canada, the U.S., the U.K. and the I.E.C. Quoting from authoritative codes & standards for each region we provide a table summarizing the current and prior wiring color code conventions used by electricians in building wiring.
For each color code table we include authority citations and links to sources of codes, books, standards and wiring guidelines. We point out with photo-examples that while wire color code theory is nice and all that, in the real world of working on existing buildings, wires are not always reliably color-coded and colors may in fact be impossible to discern. Some of the wire color images here were adapted from data provided by the Malta Resources Authority's excellent document on Harmonisation of Wiring Colour Codes - cited below.
Building Electrical Wiring Color Codes & Conventions for 120V or 240V A/C Circuits
This new type NM-B 14-3 electrical wire has color coded conductors that are easy to spot and understand:
Black - use for line voltage or "hot" wire
Red - a second line voltage or "hot" wire
White - neutral
Bare - protective ground
But as we will illustrate below, on some older buildings spotting any color at all in the wiring insulation or jacket can be difficult or even impossible. Here are links to the electrical wiring color code conventions used by various countries.
1. 2012 Canadian Electrical Code (CEC) - see http://shop.csa.ca
5060 Spectrum Way, Suite 100
Canada, L4W 5N6
Toll-Free: (800) 463-6727
Tel: (416) 747-4000
Fax: (416) 747-2473
1707-94 Street North West
Canada, T6N 1E6
Main: (780) 450-2111
Sales: (780) 490-2007
Fax: (780) 490-2059
This knob-and-tube electrical wiring photo has useful information for the electrician or building inspector.
First we can see that if we're in luck, the fabric portion of the wiring insulation may be intact and may clearly show that one conductor is white (neutral) and the other black (hot). With age the white insulation may have become tan or even brownish in color.
Second I'm a bit nervous about how that white wire is stripped back and is in contact with the hot black wire (arrow).
Finally, of course there is no protective ground on this circuit - we've got just two wires with which to contend.
120V / 240V A/C Electrical Wiring Color Codes & Conventions: U.K. United Kingdom
New wiring colour codes replaced existing red & black phase & neutral conductors (left) with brown and blue (right) beginning in 2005. Where extensions or new work can result in mixed wiring colours, a warning must be fixed near the distribution board stating: CAUTION: this installation has wiring colours to two versions of BS 7671. Great care should be taken before undertaking extension, alteration or repair that all conductors are correctly identified.
Regulating authority, IEC AC
I.E.E. Regulations (UK Standard BS 7671:2001) Requirements for Electrical Installations, IEE Wiring Regulations, Sixteenth Edition Amendment No. 2: AMD 14905, March 2004
"New Fixed Wiring Colours - A Practical Guide", www.nicelc.org.uk
"The IEE, ELectrician's Guide to the building regulations, including Approved Document P: Electrical Safety in Dwellings, Chapter 11" Malta Resources Authority, "Harmonisation of Wiring Colour Codes, Practical Guidelines",
Three phase wiring colour codes & color changes are shown just below:
This wiring shown above - well don't even think about figuring this out by color codes. Someone has just grabbed a piece of yellow wire and a blue wire, left an open splice, and jury-rigged something (not shown in our photo).
But when you see obviously amateur electrical--wiring like this it's a red flag to watch out, asking "what else did this fellow wire in this building?"
120V / 240V A/C Electrical Wiring Color Codes & Conventions: Europe - IEC
Wire Insulation Color
Alternative Wire Colors
Line voltage, single phase
Abbreviation: BN, BK
Line voltage, 3-phase
L1 is brown, black alternate
Line voltage, 3-phase
L2 is black, brown is an alternate
Line voltage, 3-phase
L3 is grey, brown and black are alternates
Abbreviation: GY, BN, BK
Green + Yellow stripe
Protective Earth wire
Regulating authority, IEC AC
Table of Wire Color Code Abbreviations 
Color Abbreviation Code
Ivory (Cream in some countries)
Natural (no pigmentation)
Smoke (light gray)
 In the U.S. UL (the Underwriter's Laboratory) has published wiring color acronyms and abbreviations. We have included the standard wiring color code abbreviations along witht the full color name in our tables of wire color standards in the article above. - retrieved 24 Feb 2014, original source: http://industries.ul.com/plastics-and-components/plastics/color-codes-and-abbreviations
(Mar 12, 2014) Keith E. Davis said:
Tell me is there an excepted convention as to the abbreviations of electrical wiring color codes?
In the U.S. UL (the Underwriter's Laboratory) has published wiring color acronyms and abbreviations. We have included the standard wiring color code abbreviations along witht the full color name in our tables of wire color standards in the article above. Thanks for asking.
Also see UL Standard 83 - Thermoplastic-Insulated Wires and Cables
Question: ok to reverse red and black wires?
(July 18, 2014) Eric said:
Does it matter if the red wire and black be reversed?
Eric without knowing what's being wired all we can say is ... Yes it might.
Generally in house wiring the red wire is a second 120V circuit on a different "phase" such that it can either provide 120V to a device or if wired along with the black wire to two terminals on some devices (such as a 240V motor) the circuit will be provided with 240V. In a 240V circuit generally which terminal gets the red and which the black won't matter.
Question: wiring an electric 600V water heater in Canada
(Sept 11, 2014) Bob said:
For Canada, 600V unit, water heater, does the ground wire have to be green/yellow or just green?
I'm referring to internal wiring, sorry.
Bob Here's a quick summary of colour conventions for the protective ground wire:
The protective ground wire (listed as green-yellow in CURRENT codes & standards) is green with yellow stripe in the UK and IEC.
In the U.S. the ground wire might be bare, or green-yellow (preferred) or green (alternative)
In Canada the ground wire (Protective Ground or labelled PG) can be green-yellow OR green.
Ask a Question or Search InspectApedia
Use the "Click to Show or Hide FAQs" link just above to see recently-posted questions, comments, replies, try the search box just below, or if you prefer, post a question or comment in the Comments box below and we will respond promptly.
Simpson 260® Series 6XLM
Volt-Ohm-Milliammeter Instruction Manual, retrieved 9/5/2012, original source: http://www.simpsonelectric.com/uploads/File/datasheets/260-6xlm.pdf, [copy on file as Simpson_260-6xlm.pdf]
Home Inspection Education Home Study Courses - ASHI@Home Training 10-course program. Special Offer: Carson Dunlop Associates offers InspectAPedia readers in the U.S.A. a 5% discount on these courses: Enter INSPECTAHITP in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
The Home Reference Book, a reference & inspection report product for building owners & inspectors. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
The Home Reference eBook, an electronic version for PCs, the iPad, iPhone, & Android smart phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter inspectaehrb in the order payment page "Promo/Redemption" space.
The Illustrated Home illustrates construction details and building components, a reference for owners & inspectors. Special Offer: For a 5% discount on any number of copies of the Illustrated Home purchased as a single order Enter INSPECTAILL in the order payment page "Promo/Redemption" space.
The Horizon Software System manages business operations,scheduling, & inspection report writing using Carson Dunlop's knowledge base & color images. The Horizon system runs on always-available cloud-based software for office computers, laptops, tablets, iPad, Android, & other smartphones.
Roger Hankey is principal of Hankey and Brown home inspectors, Eden Prairie, MN. Mr. Hankey is a past chairman of the ASHI Standards Committee. Mr. Hankey has served in other ASHI professional and leadership roles. Contact Roger Hankey at: 952 829-0044 - email@example.com. Mr. Hankey is a frequent contributor to InspectAPedia.com.
Arlene Puentes, an ASHI member and a licensed home inspector in Kingston, NY, and has served on ASHI national committees as well as HVASHI Chapter President. Ms. Puentes can be contacted at firstname.lastname@example.org
Wikipedia provided background information about some topics discussed at this website provided this citation is also found in the same article along with a " retrieved on" date. NOTE: because Wikipedia entries are fluid and can be amended in real time, we cite the retrieval date of Wikipedia citations and we do not assert that the information found there is necessarily authoritative.
Books & Articles on Building & Environmental Inspection, Testing, Diagnosis, & Repair
The Home Reference Book - the Encyclopedia of Homes, Carson Dunlop & Associates, Toronto, Ontario, 25th Ed., 2012, is a bound volume of more than 450 illustrated pages that assist home inspectors and home owners in the inspection and detection of problems on buildings. The text is intended as a reference guide to help building owners operate and maintain their home effectively. Field inspection worksheets are included at the back of the volume. Special Offer: For a 10% discount on any number of copies of the Home Reference Book purchased as a single order. Enter INSPECTAHRB in the order payment page "Promo/Redemption" space. InspectAPedia.com editor Daniel Friedman is a contributing author.
Or choose the The Home Reference eBook for PCs, Macs, Kindle, iPad, iPhone, or Android Smart Phones. Special Offer: For a 5% discount on any number of copies of the Home Reference eBook purchased as a single order. Enter INSPECTAEHRB in the order payment page "Promo/Redemption" space.