How to Install USB Sockets

The USB system has come a long way from its humble beginnings. In the 1990s it was just a standardised way of transferring signals between things like PCs, printers and keyboards – at a stroke, replacing all those different PC connectors for every peripheral.

As time went on, the system became better able to carry enough electric current to be useful for powering certain devices or charging batteries. Now, all phones have a USB charger, and Apple announced in September 2023 that its phones will be charged by USB-C instead of the Lightning port (although the power end of the cable was always USB compatible).

Because USB charging is so common, you can now get wall sockets for your home that have a USB socket built in. That’s a great idea, because it frees up a three-pin socket that would have been used for a charger. Also, they aren’t going to buzz away all day using energy – who unplugs their USB adapter when not in use?

Choosing a USB wall socket

The easiest way to choose a USB socket is to get a new version of the socket that’s already in place. So if it's a single socket, get a single USB socket, and if it’s a double – well, you can guess. That means you can replace the socket yourself as it’s a like for like change, which means you only need to be competent, not a qualified electrician as per the Building Regulations, Electrical safety: Approved Document P.

Now, consider your needs. You can get a single wall socket with two USB sockets, but most match the number of 3-pin sockets with the number of USBs, so most double sockets have two USB slots, like this one.

You can also choose to get a wall socket with a USB-C socket, which might be useful too. As you’ll only be using it for charging, rather than data transfer, you probably don’t need this just yet, as most USB-C charger cables go to a standard USB plug at the other end. However, if you want to future-proof your phone charging, having both types of USB is a smart move. Many USB sockets are available with a fast charging function up to 45W, which is great for devices that support it like a lot of modern Android phones, or 15W for Apple.

Installing the socket

We’ve written a more in-depth account on how to do a like-for-like socket swap here (LINK TO SOCKET INSTALLATION GUIDE). Installing a USB-capable socket will be identical in every way, so below, we’ll quickly run through the steps one by one, but please refer to the other article if you need to go into greater depth.

1. Check the power

Make sure the power is working by plugging in a lamp, radio or such like, and turn it on. If you have a voltage detector and you know how to use it safely, do that as well.

2. Switch off the power at the consumer unit

You might call your consumer unit a fuse box, but that’s the old name – they now have trip switches rather than fuses that burn out and need replacement. The consumer unit will probably be next to your electricity meter. 

The individual circuits will be labelled, e.g. “upstairs sockets” or “downstairs lights”. Switch off the circuit that applies to the socket you’re working on. If you want to be extra safe, turn off the main switch, which will cut electricity to your whole property. Leave a note on the unit to make sure no one turns it back on.

3. Remove the faceplate

Has the light or radio gone off? If it hasn’t there’s something seriously wrong with your wiring! Call an electrician immediately. Assuming it is off, unplug it and again, test with a voltage tester if you have one. Now, unscrew the faceplate and pull it free – it’ll still be attached to the wires, so don’t pull too hard.

4. Release the faceplate

Now, look at the different coloured wires and where they connect to on the old socket. They should be:

  • brown (or red) → ‘L’ (live) terminal
  • blue (or black) → ‘N’ (neutral) terminal
  • yellow & green → ‘E’ or ‘⏚’ (earth) terminal.

Undo the terminal screws, which will release the wires. When the last wire has been released, the faceplate can be put to one side.

5. Locate the terminals on the new socket

Have a look at the back of the new USB wall socket, and note where the L, N and E (⏚) terminals are – they might be in different positions to those of the old one.

6. Attach the wires

One wire at a time, connect:

  • the brown (or red) wire to the ‘L’ (live) terminal
  • the blue (or black) wire to the ‘N’ (neutral) terminal
  • The yellow & green wire to the ‘E’ or ‘⏚’ (earth) terminal

Tighten them up firmly enough that they can’t come loose, but not so tightly that you damage them. Make sure the terminal and the screw are clamping the copper wire itself, not the coloured insulation, as that will stop it working or, in the case of Earth, make it unsafe.

7. Attach the socket

With the wires firmly in place, press the faceplate back against the back box (sunk into the wall) or pattress box (standing proud of the wall), and re-tighten the screws holding it in place.

8. Switch back on at the consumer unit

Now, if all looks well and there are no cables trapped between the faceplate and back box, you can turn on the power at the consumer unit. The new socket should all be working fine now, but test each three-pin and USB socket to make sure it’s in working order. You can give it a quick test with your tester if you have one, just for a little extra peace of mind.

Now, as if by magic, you don’t have to go rooting around in drawers or arguing over whose turn it is to use the USB adapter – although you might have to fight for the chair next to the socket. Ah well, it looks like it’s time to install another USB wall socket!