United States

• The United States follows the U.S. National Electrical Code which only mandates that the neutral wire color be white or gray and that the protective ground be yellow, green or bare, meaning uncovered by a color. Live wires such as the single-phase lines are either black or red while L1 three-phase lines are either black or brown. L2 three-phase lines are either red or orange and L3 three-phase lines are either blue or yellow.
  
  

Europe

• The power system in Europe uses the International Electrotechnical Commission's color codes for wiring in AC power systems. Because of this, the wiring color is slightly different from that of the United States. The ground line, for example is either green or yellow, while the L2 line is black. Single-phase lines along with L1 three-phase lines are brown and L3 three-phase lines are gray. Neutral lines throughout most of Europe are blue. Before the IEC standardizations, wiring was not so distinct. Older wiring colors exhibited phase power lines from L to L3 with colors of either brown or black.
  
  

United Kingdom

• The United Kingdom, including England, Scotland, Northern Ireland and Australia, is currently following the IEC's standards for electrical wiring. Like Europe, this mandates that the ground, or protective earth, line is colored either green or yellow, the neutral blue, L and L1 colored brown, L2 colored black, and L3 colored gray. Older houses that do not follow this code are still common in the U.K. and feature a neutral line that is black and not blue, single line L and L1 three-phase lines that are red, L2 lines that are yellow and L3 electrical wires that are blue.
  
  

Canada

• Like the United States, Canada does not follow the IEC's commission recommendations, but instead uses the Canadian Electrical Code, or CEC. Under this code, the protective ground wire is green or yellow while the neutral line is white. Live wires such as the single phase L and the L1 three-phase lines are red, although single-phase lines are sometimes black. L2 lines are black and L3 lines are blue.