DIY GUIDE · ELECTRICAL

How to replace a socket or light switch faceplate yourself
An hour a faceplate. £3–£15 for the accessory, £25–£46 once for a two-pole tester.

Same box, same cables, same kind of socket or switch. Isolate, prove dead, swap, test — and nothing new.

DIFFICULTY
Moderate
part of the job only
TIME
An hour
per accessory, most of it isolating, proving dead and checking the old connections
MATERIALS
£3–£15
a white plastic double socket or switch costs a few pounds; metal finishes cost more
A PRO CHARGES
£30–£250
typically £75
  • Every step, start to finish
  • Checked October 2026 — sources at the end
  • Honest about when to call a pro

FIRST, THE HONEST ANSWER

Do it yourself, or get a fitter?

Do it yourself if…

  • The new socket or switch is the same kind as the old one, on the same back box
  • The cables are modern PVC, brown and blue or red and black, with an earth
  • You can find the right circuit breaker or fuse and switch it off, and you have a two-pole voltage tester
  • The accessory is in a living room, bedroom, hall or kitchen, not in a bathroom or shower room

Get a pro if…

  • You want a socket added, moved, or a single changed for a double on a new spur
  • The old accessory is scorched, melted, smells of burning, or the cables behind it are discoloured
  • The cables are old rubber, crumbling, or have no earth conductor
  • It is in a bathroom, the consumer unit needs anything at all, or you are not certain which circuit you have isolated

Safety first

  • Switch off the circuit at the consumer unit and lock or tape the breaker off, with a note on it, so no one switches it back on while you work. HSE's guidance for electrical work is to isolate securely and check it is dead before you start.
  • Prove the circuit dead at the accessory with a two-pole voltage tester, testing it on a known live socket before and after. A non-contact pen or a neon screwdriver is not proof of dead.
  • Switch off the whole consumer unit at its main switch if you cannot be sure which breaker feeds the accessory; many houses have circuits that are not labelled correctly.
  • Do not work on anything with signs of overheating — scorch marks, melted plastic, a burning smell. That is a fault on the circuit, not a worn faceplate.
  • Never restore the power with the faceplate off or a conductor loose. Fix the accessory to the box first, then switch on and test.

Stop here: Stop here: anything new, the consumer unit and special locations

A like-for-like replacement of an accessory on its existing circuit is the householder's limit. In England, a new circuit, a new or replacement consumer unit, and any new work or alterations around a bath or shower are notifiable under Part P of the Building Regulations, with guidance in Approved Document P, unless a registered competent person does and certifies them. Wales has its own Approved Document P under its own building regulations, and there additions in kitchens, bathrooms and outdoors are never exempt. Scotland works to building standard 4.5 and the wiring regulations, BS 7671, with a building warrant needed for some electrical work. Northern Ireland's building regulations have no Part P-style notification scheme for home wiring, but the work must still be done safely and its landlords must have installations tested. How to hire a socket and switch fitter →

MATERIALCOVERAGEFOR THIS JOB
Socket or switchSame type and gang count as the old one, made to the right British StandardOne
Earth sleevingGreen and yellowA short length
Back box screwsUsually M3.5, length to suit the boxTwo
Insulating tapeFor labels only; not as a repair to damaged insulationOne roll

How many accessories, how much time

Time = accessories × 45 minutes + 20 minutes to isolate and test. Six faceplates in one room is 6 × 45 + 20 = 290 minutes, about five hours.

Isolate and prove dead again for every accessory, even on the same circuit; it takes a minute and catches a wrongly labelled breaker.

Like for like

Buy the same kind of accessory: a double switched socket for a double switched socket, a one-gang two-way switch for a one-gang two-way switch. Count the gangs, check whether the old switch has two or three terminals per gang, and look at the back of the old one before you shop. Changing type — a switch to a dimmer, a socket to one with USB outlets — is still a like-for-like swap if the wiring is the same, but read the new accessory's instructions first.

Back box depth

Flat-plate and screwless accessories need space behind them. One maker's switchsocket we checked fits a 25 mm deep box, with a 35 mm box suggested for more wiring space. If the old accessory sat on a shallow box and the new one is deeper, the cables will be crushed; buy a slim accessory or have the box replaced.

Screw or screwless terminals

Traditional accessories clamp each conductor under a screw. Newer ones use lever or spring terminals that grip the conductor without a screw. Both are fine. Lever terminals take one conductor each on the model we checked; if two cables share a terminal on the old accessory, check the new one accepts that, or use a screw-terminal accessory.

Metal faceplates and earthing

A metal faceplate, and a metal back box, must be earthed. The maker's instructions for the socket we checked say to connect a sleeved earth link between the socket's earth terminal and the back box's earth terminal. If there is no earth conductor in the box at all, stop: that is a wiring fault.

Dimmers and LED lamps

A dimmer swap needs a dimmer rated for the lamps on that circuit; LED lamps draw far less power than old bulbs and many older dimmers will flicker with them. Check the dimmer's minimum and maximum load against the total wattage of the LED lamps, and that the lamps are marked dimmable.

Standards marking

Sockets and plugs in British homes are made to BS 1363. Buy from a known retailer and look for that number on the packaging or the accessory; cheap online sockets without it can have thin contacts that overheat.

Photograph the back of the old accessory before you disconnect anything.
Buy one more back-box fixing screw than you need; the old ones are often rusty or short.

THE PART THAT DECIDES THE FINISH

Before you start — what you find behind the faceplate

Once the circuit is proved dead, unscrew the old faceplate and ease it forward. What you see decides whether the swap is yours.

Modern cable, one or two sets of conductors

Brown, blue and a bare or sleeved earth, or the older red, black and earth.

  1. Photograph which conductor goes to which terminal
  2. Check the insulation is sound, not brittle or discoloured
  3. Check the earth conductors are sleeved green and yellow; add sleeving if they are bare
  4. Note whether the back box is metal or plastic
A light switch with extra conductors

Two-way or intermediate switching, or a switch with a borrowed neutral.

  1. Count the terminals in use on the old switch: COM, L1 and L2 on a two-way switch
  2. Label each conductor with tape before disconnecting it
  3. Check the new switch has the same terminals
  4. If a conductor is marked as a switched line with brown tape or sleeving, keep it on the same terminal
Metal back box

A steel box sunk into the wall.

  1. Look for an earth terminal inside the box and a link to the accessory's earth terminal
  2. If there is no link, plan to fit one from sleeved earth conductor
  3. Check the box's fixing lugs are not bent and the screw threads are sound
  4. Check no conductor's insulation is chafed on the box's edge
Signs of trouble

This is where the swap stops.

  1. Scorching, melted plastic or a burnt smell on the old accessory or the cables
  2. Old rubber-insulated cable, black and crumbling, or cable with no earth at all
  3. More cables than you expected, or ones that do not match any terminal
  4. Put the old faceplate back loosely, leave the circuit off, and call an electrician

THE JOB

How to swap the socket or switch

  1. Set up: isolate the circuit and lock it off

    15 min

    Read the cards above so you know what to expect behind the plate. At the consumer unit, switch off the breaker for the circuit, or the main switch if you are unsure. Tape over the breaker with a note saying work is in progress, or fit a lock-off if your board takes one. Plug a lamp into the socket you will work on, or flick the light switch, to see that it has gone off.

    • Labels on boards are often wrong; check, do not trust
    • Tell everyone in the house what you are doing
    • Have a torch, because the lights may be on the same circuit

    Mistake to avoid: Switching off one breaker and trusting the label. Sockets in one room can be on two circuits, and the one you are about to touch is the one still live.

  2. Prove it dead

    10 min

    Test your two-pole tester on a known live socket elsewhere. Then unscrew the faceplate, ease it forward without touching the terminals, and test between every pair of terminals: line and neutral, line and earth, neutral and earth. Then test the tester again on the known live supply. Only if all three tests read dead, and the tester works before and after, is it dead. This is the prep that the cards above depend on.

    • Test every set of conductors in the box; a box can hold two circuits
    • Keep your fingers behind the tester's finger guards
    • If anything reads live, put the plate back and find the right breaker

    Mistake to avoid: Using a non-contact pen and taking its silence as dead. These pens miss voltage through cable shielding, dead batteries and the user's own position, and they never prove a circuit dead.

  3. Photograph and disconnect

    10 min

    Photograph the back of the old accessory with every conductor visible. Label each conductor or set with tape if there is any doubt. Undo the terminal screws, or lift the levers, and draw each conductor out. Check the copper ends: they should be bright, not blackened, and cut cleanly.

    • On a two-way switch, label COM, L1 and L2 before anything comes off
    • If two conductors share a terminal, keep them together
    • Check for blackening on the old terminals; heat damage means a call to an electrician

    Mistake to avoid: Disconnecting everything at once and then guessing. On a two-way switch, getting COM wrong makes the light work from one switch only.

  4. Prepare the conductors

    15 min

    If an end is nicked, blackened or bent, cut it back square and strip fresh insulation with wire strippers to the length marked on the new accessory; the socket maker we checked asks for 10 mm of bare conductor. Slide green and yellow sleeving over any bare earth. Twist stranded conductors neatly so no strand stands out.

    • Strip only as much as the terminal takes; bare copper outside a terminal is a hazard
    • Keep enough slack for the conductors to reach the terminals without strain
    • Never cut back so far that a conductor will not reach

    Mistake to avoid: Leaving bare copper showing outside the terminal. It can touch another conductor or the metal box when the accessory is pushed back.

  5. Connect the new accessory

    15 min

    Connect each conductor to the same terminal it came from: brown or red to L, blue or black to N, green and yellow to the earth terminal. The socket maker's colour codes are brown and blue for wiring after April 2004 and red and black before. Tighten each screw firmly, or close each lever fully, then tug each conductor gently to check it is held. On a metal box, connect a sleeved earth link from the accessory to the box's earth terminal.

    • One conductor per lever terminal, unless the accessory says otherwise
    • A loose terminal heats up under load; a firm screw is the difference
    • Insulation should reach the terminal, with no bare copper showing

    Mistake to avoid: Mixing up line and neutral. The socket works, but its switch now isolates the neutral, and the appliance inside stays live with the switch off.

  6. Fit the accessory to the box

    10 min

    Fold the conductors neatly into the box so none is trapped behind a lug or across a screw hole. Offer the accessory up square and fix it with the screws, tightening them evenly. The maker warns against over-tightening, which distorts the faceplate. Check it is level and flush with the wall.

    • Push conductors to the back of the box, not round the sides where the screws go
    • Use new screws if the old ones are rusty or too short
    • A slight gap on an uneven wall is normal; do not crack the plate pulling it flat

    Mistake to avoid: Driving a fixing screw through a trapped conductor. The insulation is pierced and the box becomes live.

  7. Restore the power and test

    10 min

    Remove the tape or lock from the breaker and switch the circuit on. For a socket, plug in a lamp and switch it on and off at the socket; a plug-in socket tester shows whether line, neutral and earth are in the right places. For a switch, check the light works, and from both switches on a two-way circuit.

    • If the breaker trips at once, switch off and recheck every connection
    • A plug-in socket tester costs little and catches a reversed line and neutral
    • Check the accessory does not get warm after a few minutes under load

    Mistake to avoid: Assuming it is right because the lamp lights. Line and neutral swapped still light a lamp, and only a tester shows it.

  8. Check after a day

    5 min

    Look at the new accessory the next day. Feel it with the back of your hand after something has been plugged in for an hour. It should be cool. Note what you changed and the date on a label inside the consumer unit's door.

    • Warmth at a socket means a loose connection or an overloaded adaptor
    • A buzzing or crackling noise means switch off and call an electrician
    • Replace the label on the breaker if you found it was wrong

    Mistake to avoid: Ignoring a socket that feels warm. Heat at a terminal is the start of a fire, not a quirk.

The mistakes that show

  • Trusting a breaker label instead of proving dead at the accessory
  • Using a non-contact pen as proof of dead
  • Swapping line and neutral on a socket
  • Leaving bare earth conductors unsleeved, or a metal box unearthed
  • Swapping an accessory that showed signs of overheating

Stop here and get an electrician

  • You want a new socket, a moved socket, or a new spur
  • The old accessory or the cables show scorching, melting or a burning smell
  • The cables are old rubber, crumbling, or there is no earth
  • The accessory is in a bathroom or shower room, or anything at the consumer unit is involved
How to hire a socket and switch fitter →

Breaker trips when switched back onA conductor is touching the wrong terminal or the box, or a screw has pierced a cable. Switch off, prove dead, take the accessory off and check every connection and the cable runs in the box.
Socket tester shows reversed polarityLine and neutral are swapped. Isolate, prove dead, and swap them so brown or red is on L and blue or black is on N.
Light only works from one switch on a two-way circuitThe COM and L1 or L2 conductors are swapped. Isolate, prove dead and check them against the photograph.
New faceplate will not sit flatThe back box is too shallow, the conductors are bunched, or the box is skewed. Refold the conductors, or use a slimmer accessory.
New dimmer flickers with LED bulbsThe dimmer's minimum load is above the LED total, or the lamps are not dimmable. Fit an LED-rated dimmer matched to the load, and dimmable lamps.
Socket feels warmA loose terminal or an overloaded adaptor. Isolate, prove dead, and tighten every terminal; if it still warms, call an electrician.
Faceplate cracked when tighteningThe screws were over-tightened on an uneven wall. Fit a new plate and tighten evenly just until it is firm.
Conductor will not stay in a lever terminalToo much or too little bare copper, or a stranded conductor not twisted. Strip to the marked length and close the lever fully.

WHAT YOU SAVE

What it costs to do it yourself

White double switched socket or a switch£3–£15
Two-pole voltage tester£25–£46
Plug-in socket tester£8–£17
Total, one accessory with testers bought once£36–£78
DIY total£3–£15
A socket and switch fitter charges per point
LOW
£30
TYPICAL
£75
HIGH
£250
Socket & Switch Installation price guide →

Guide prices compiled by the Locufy team from published Irish and UK provider price lists and 2026/27 cost guides. Updated 2026.

An electrician's guide price per point is close to the cost of the testers, but the testers are bought once; the saving grows with every faceplate after the first.

RATHER NOT?

Socket and switch fitters near you, with prices shown

The ones who cover your area, nearest first, with one score from every review. No account needed to look.

Or post the job free and let them come to you.

Label the board

Correct any breaker label you found wrong, and note the date and what you changed inside the consumer unit door.

Store the tester properly

Keep the two-pole tester with its leads and probe caps in a dry place, and check it on a known live socket before every use.

Dispose of the old accessory

Old sockets and switches are electrical waste. Take them to the electrical or small-appliances container at your council's household waste recycling centre; do not put them in the household bin. Find your centre on the council website or the recycling pages for your nation.

Get a periodic check

If you found old cable, no earth or a wrongly labelled board, have an electrician carry out an electrical installation condition report on the whole house.

Replacing a socket or light switch like for like: questions people ask

Replacing a socket like for like on the same box and cables is not notifiable in England, so a competent householder can do it. Adding, moving or anything near a bath or shower is different, and Wales, Scotland and Northern Ireland have their own rules.

Switch off the circuit's breaker at the consumer unit, or the main switch if you are not sure which breaker it is. Then prove it dead at the socket with a two-pole tester before you touch anything.

Brown or red to L, blue or black to N, green and yellow to earth. Brown and blue are the colours in wiring after April 2004; red and black before.

No. It can miss voltage and cannot prove a circuit dead. Use a two-pole voltage tester, checked on a known live supply before and after.

That is not a like-for-like swap. A double faceplate usually needs a larger back box cut into the wall, and anything that adds a cable or a spur is new work. Leave it to an electrician, who can also check the circuit can take it.

Locufy's UK price guide puts socket and switch installation at £30–£250 per point, typically £75 — the same three figures as the strip at the top of this page.

MORE GUIDES

More DIY guides

Switching to LED and replacing a light fitting like for likeReplacing an extractor fan like for likeFitting solar and low-voltage plug-in garden lightingPainting a roomFitting a battery carbon monoxide alarmRunning an Ethernet cable and fitting a data socketFitting a battery or plug-in security camera
All 90 DIY guides →How to hire a socket and switch fitter →Socket & Switch Installation price guide →Socket and switch fitters on Locufy →

Sources — checked October 2026

  1. MK Electric — screwless 13A switchsocket installation instructions and technical data
  2. HSE — electrical safety: frequently asked questions (isolate and check dead)
  3. HSE — HSG85 Electricity at work: safe working practices
  4. gov.uk — Approved Document P: electrical safety in dwellings (England)
  5. gov.uk — building work, replacements and repairs to your home (England)
  6. gov.wales — building regulations: electrics
  7. gov.scot — Building Standards Technical Handbook 2022 (domestic), standard 4.5 electrical safety
  8. gov.scot — Regulation of electricians in Scotland: when a building warrant is needed
  9. Electrical Safety Standards for Private Tenancies Regulations (Northern Ireland) 2024
  10. gov.uk — recycling collections: find your council (England and Wales)
  11. mygov.scot — find your council's recycling centre (Scotland)
  12. nidirect — recycling and reusing (Northern Ireland)
  13. B&Q — price check: double sockets
  14. B&Q — price check: two-pole voltage testers
  15. B&Q — price check: socket testers