How to wire a 3-pin UK plug

Inspired by a popular UK tutorial. This guide is based on the well-known "How to wire a plug" video from the Ultimate Handyman channel — one of the most-watched UK DIY resources online. Worth a quick watch if you prefer seeing the colour-coded terminals before you pick up a screwdriver.

1. Gather what you need and turn everything off

You need a small flat-head screwdriver, a wire stripper or sharp craft knife, and the correct fuse. Make sure the appliance is unplugged from the wall before you start. Obvious, but worth saying.

Good light matters too. You are working with small terminals and fine wires, and getting them mixed up is genuinely dangerous.

2. Open the plug

Unscrew the large central screw on the back of the plug. Some plugs use a coin slot, others need a crosshead. The back cover will hinge or lift off.

Note which way round the fuse sits in its holder before you remove anything — it will save a moment of confusion later.

3. Cut back the outer cable sheath

The cable has a tough outer sheath protecting three separate inner wires. Cut this back carefully — about 40–50 mm is typically enough to reach all three terminals without pulling the cable too tight.

Use a knife or the sheath-stripping notch on your wire strippers. Score round the sheath gently rather than hacking at it. The wires inside are thin and easy to nick.

4. Strip the individual wire insulation

Each inner wire has its own coloured insulation. Strip about 8–10 mm from the end of each wire. You want enough bare copper to wrap firmly round a terminal post or clamp cleanly into a screw terminal — but not so much that bare copper is exposed outside the terminal.

Twist the copper strands together neatly after stripping. Loose strands can short against adjacent terminals.

5. Learn the UK wire colour code

This is the critical bit. In modern UK cables: Brown is Live (L), Blue is Neutral (N), and Green and yellow stripe is Earth (E).

That said — in older appliances you might find red (live), black (neutral), and green (earth). Same principle, older colours. If the wires look discoloured or frayed, stop and get the appliance checked by an electrician.

6. Connect the wires to the correct terminals

Live (brown) goes to the right-hand pin when the plug is face-down with the large earth pin at the top. Neutral (blue) goes to the left-hand pin. Earth (green/yellow) goes to the top pin, which is slightly longer than the others.

Tighten each terminal screw firmly. Give each wire a gentle tug to confirm it is held. A loose connection generates heat, which is how plugs catch fire.

7. Secure the cable clamp

Most plugs have a cable grip or clamp near the entry point. Tighten this onto the outer sheath — not on the inner wires themselves. The clamp should take any strain if the cable gets pulled, protecting the terminal connections.

If the cable is unusually thick or thin for the plug, make sure the clamp bites properly. A loose grip here is almost as bad as a loose terminal.

8. Fit the correct fuse and close up

The fuse rating should match the appliance. General rule: 3 A for appliances up to 700 W (table lamps, small radios), 13 A for everything above that (kettles, toasters, power tools). When in doubt, check the appliance label for wattage.

Clip the fuse into its holder, refit the back cover, and tighten the central screw. Plug in and test.

When to call a handyman

Call Richard if the cable is damaged more than a few centimetres from the plug, if the plug itself is melted or scorched, or if you are not sure which wires are which. Never use old red-and-black wiring in a modern plug without checking it first. Some jobs look simple until they are not.