UK wiring colours: Old vs. new

What are the current UK wiring colours?

The UK now uses a standardised wiring colour system designed to make electrical installations safer and easier to understand.

The current UK wiring colours are: 

• Live wire: Brown 
• Neutral wire: Blue 
• Earth wire: Green and yellow stripes

These colours are used in all modern UK homes and electrical installations.

What does the live wire do?

The live wire carries electricity from the power source to a switch, socket or appliance.

Because it carries current, the live wire is the most dangerous wire to touch if the power is still on. In current UK wiring colours, the live wire is brown.

What does the neutral wire do?

The neutral wire carries electricity back from the appliance to the power source, completing the circuit.

Neutral wires also help distribute electrical loads evenly across circuits. In modern UK wiring, the neutral wire is blue.

What does the earth wire do?

The earth wire is an important safety feature within an electrical system.

Its job is to protect against electric shock by providing a safe path for electricity to travel to the ground if there’s a fault. This helps reduce the risk of injury and damage.

In current UK wiring colours, the earth wire is green and yellow in a striped pattern or can be a bare copper wire with a green and yellow striped sleeve.

Bonus: Strapper cables

Strapper cables are found mostly in hallways, stairwells, and large rooms where controlling a single light from multiple access points is necessary. They would also be used for extractor fans or controllers.

While older strapper cables use red, yellow and blue cable colours to connect an outlet to different switches, modern standard cables often use brown, grey and black for the strapper wires.

If you’re a DIYer and you come across a strapper wire while you’re doing any basic electrical work, it’s best to call a qualified electrician to finish the job. They can be tricky to get right if you’re not properly trained.

Old wiring colours in the UK

Before the current standards were introduced, the UK used a different wiring colour system.

The old UK wiring colours were:

• Live wire: Red
• Neutral wire: Black
• Earth wire: Green and yellow

In very old systems installed before 1977, the earth wire may be entirely green rather than green and yellow striped.

Because of this, some homes in the UK may still contain old wiring colours, newer wiring colours, or even a mixture of both.

When did the UK wiring colours change?

The UK wiring colours changed in 2004 under updated wiring regulations.

The change was introduced to align UK electrical standards with European regulations and help reduce confusion during electrical work. Standardising wiring colours also improved safety for electricians and homeowners.

Because some older homes still contain previous wiring systems, electricians today can often come across both old and new wire colours in the same property.

Old vs. new wiring in the UK: What’s changed?

If you’re unsure about the wiring in your home, think you may have outdated electrics, or suspect faulty wiring, it’s always safest to contact a qualified electrician. Electrical work can be dangerous if carried out incorrectly, particularly in homes with mixed wiring systems.

Is old wiring covered by home electrical cover?

If it was installed correctly at the time of installation, even older wiring is covered by HomeServe Electrics cover, giving you peace of mind even in older homes. All home emergency cover policies are different, so be sure to check your policy details when you’re comparing providers.

Explore reliable cover for your home’s electrics

Electrical problems can happen without warning, whether it’s faulty wiring, broken sockets or unexpected electrical faults.

With HomeServe’s Electrics cover, you’ll have access to qualified electricians who can help get things back up and running quickly—and most importantly, safely. So, whether you’re dealing with older wiring or unexpected electrical issues, you can count on us to be there when you need help most.