Important safety note

This guide is for replacing an existing socket, not adding new ones or altering circuits. If you’re unsure about anything, such as the wiring not matching what’s described, or you see scorch marks, brittle insulation, or loose cables, stop and call a professional.

Get professional help if:

• You find mixed old and new colours in the same socket
• There’s no earth wire
• The back box is damaged
• The circuit keeps tripping

Step 1: Turn off the power

Go to your consumer unit (fuse box) and switch off the circuit supplying the socket. If you’re not sure which one it is, turn off the main switch. Then use the voltage tester to test the socket. Only proceed once you’re 100% sure it’s dead.

Step 2: Remove the socket faceplate

Undo the two screws holding the socket to the wall. Carefully pull it forward but don’t force it, the wires should have some slack, but you don't want anything accidentally coming loose yet.

Step 3: Identify the wiring colours

Depending on the age of the electrics you will have different wiring colours as UK wiring colours changed in 2004:

Modern wiring (post-2004):

• Live (L) - Brown
• Neutral (N) - Blue
• Earth (E) - Green & yellow

Old wiring (pre-2004):

• Live (L) - Red
• Neutral (N) - Black
• Earth (E) - Green (sometimes bare copper with green sleeving)

To be completely sure, take a photo before disconnecting anything, ensuring you capture each wire, each terminal and its letter (L, N or E).

Step 4: Disconnect the wires

Loosen the terminal screws and remove the wires one at a time. You may see two wires in one terminal. This is normal for ring circuits. Try to keep them grouped together for when you reconnect them. If you notice insulation is brittle or crumbling, stop and call an electrician.

Step 5: Connect the new socket

Match each wire to the correct terminal using the colouring guide in step 3, or the photo you took. Push each wire fully into its terminal and tighten firmly, don't over do it as you could misthread the screw/damage the socket. Give each wire a gentle tug to confirm it’s properly clamped.

Step 6: Refit the socket

Carefully fold the wires back into the back box ensuring no sharp bends or trapped insulation. Tighten each screw gradually, leaving just enough slack so you can ensure the socket is level. If you really want to be sure, use a short spirit level before fully tightening into place.

Step 7: Restore power and test

Turn the power back on at the consumer unit. Test the socket using a lamp or phone charge, and check for proper operation, ensuring no buzzing, heat, or flickering. If you notice anything wrong, turn the power off immediately and recheck for loose wires.