What the job involves
The consumer unit is the box that splits the incoming electricity supply into the separate circuits in your home: lighting, sockets, cooker, shower and so on. It is what most people still call the fuse box. Replacing it means removing the old unit and fitting a new one with modern protective devices, then reconnecting every circuit to it.
A typical job covers:
- Isolating the supply. For this the electrician may need the supplier or network operator to remove the main fuse seal, or the work may be done with the supply off at the meter.
- Removing the old unit and checking the condition of the tails (the heavy cables from the meter) and the earthing and bonding.
- Fitting a new metal-enclosed consumer unit with RCD protection and individual circuit breakers.
- Labelling each circuit and reconnecting it.
- Testing every circuit before the supply is switched back on.
- Issuing an Electrical Installation Certificate, and notifying building control or registering the work through the electrician's competent person scheme.
The certificate is the proof the work was done and tested to the wiring regulations (BS 7671). You will need it when you sell the house, and your insurer may ask for it. The job is notifiable under building regulations in England and Wales, so it should be done by someone registered to self-certify, or checked by building control. Part P is the part of the regulations that covers this.
What affects the price
Two consumer unit jobs that look the same can differ quite a lot in cost. These are the main reasons.
- Number of circuits. A larger unit with more ways costs more for the unit itself and takes longer to wire and test. A small flat is simpler than a large house with an extension, garage and outbuilding.
- Type and brand of unit. Basic units cost less than premium ranges. Units with surge protection, smart monitoring or extra spare ways cost more.
- Condition of existing wiring. Old rubber or cloth-covered cable, brittle insulation or poor joints may need attention before the new unit can be safely connected. Testing sometimes shows faults that have to be put right.
- Earthing and bonding. If the main earth or the gas and water bonding is missing or undersized, it has to be corrected. This adds materials and time.
- Position of the unit. Moving the unit from under the stairs to a hallway wall, say, means extending cables, making good plaster and possibly more labour. Replacing it in the same spot is the cheapest route.
- Access and layout. A unit in a cramped cupboard or at an awkward height is slower to work on. Sometimes the cupboard needs to be cleared first.
- Meter tails and cutout. If the tails are too short, damaged or too small, they need replacing. If the supplier's cutout or meter tails need work, the supplier may have to be involved, which can add cost and waiting time.
- Number of rooms with older accessories. Some electricians will recommend replacing damaged sockets or switches while they are there, which is extra to the basic job.
- Testing and certification. A thorough inspection and test of all circuits takes time. A very low price often means less testing.
- Region and demand. Labour rates vary across the UK, and busy periods can push prices up.
- Parking, access and travel. In some city areas these add to the overall cost.
The prices shown on this page reflect what other homeowners actually paid, so compare your own quote against them, bearing in mind how your house differs from a typical one.
Ways to keep the cost down
- Get several quotes from registered electricians, and make sure each one covers the same scope so you are comparing like with like.
- Keep the unit where it is unless there is a good reason to move it.
- Clear access before the electrician arrives. Empty the cupboard, move furniture and make sure there is somewhere to park.
- Choose a standard unit from a reputable make rather than a premium one with features you will not use. Do ask about surge protection, as it is often worth having.
- Ask for an inspection first if you are unsure about the state of the wiring. Knowing what is wrong before work begins helps avoid surprise extras.
- Bundle jobs. If you also want extra sockets, a new circuit or an EV charger, doing it all on the same visit usually saves on call-out time and repeat testing.
- Be flexible on dates. Some electricians offer better availability or prices outside peak times.
- Do not skimp on the certificate or testing. A cheap job without proper paperwork can cost far more to put right later.
What should be included in a quote
A good quote is itemised and clear. Look for:
- [ ] Supply and fitting of a new consumer unit, with the make and model named
- [ ] RCD protection and circuit breakers for all existing circuits
- [ ] Whether surge protection is included
- [ ] Testing of all circuits before and after the work
- [ ] An Electrical Installation Certificate
- [ ] Notification of the work to building control or through a competent person scheme
- [ ] Checking and, if needed, upgrading the earthing and bonding
- [ ] Any replacement meter tails, or a clear statement that they are not included
- [ ] What happens if testing reveals faults, and how any extra work will be priced
- [ ] Making good around the unit, or a statement that decorating is not included
- [ ] Disposal of the old unit
- [ ] VAT status
- [ ] Expected start date, duration and any period without power
- [ ] Payment terms and any deposit
- [ ] Guarantee or warranty on the work
Questions to ask an electrician
- Are you registered with a competent person scheme, and can I see proof?
- Will you notify building control, or does your scheme do it for you?
- Which consumer unit will you fit, and does it include surge protection?
- Will you test the existing circuits first, and what happens if you find a fault?
- Do the earthing and bonding meet current requirements, and will you check them?
- Will the power be off all day, and for how long at a time?
- Do you need the supplier to attend, and will that delay the job?
- Will I receive the certificate on the day or afterwards, and how soon?
- What is covered by your guarantee, and for how long?
- If extra work is needed, how will you agree it and price it before going ahead?
How long it takes and what to expect
A straightforward replacement is usually done within a working day. A larger house, a difficult location or problems found during testing can stretch it longer. Expect the power to be off for a good part of the day, so plan around fridges, freezers, broadband, medical equipment and anything that cannot be left without power. Ask the electrician to tell you in advance when the supply will be off.
On the day, the electrician will isolate the supply, take off the old unit and fit the new one. Each circuit is tested before the power is restored, and you may be asked to confirm which circuit serves which room so the labels are correct. After the work, expect some dust and perhaps a small amount of plaster repair around the unit.
Afterwards, you should get your Electrical Installation Certificate, either straight away or within a short time. Keep it with your house documents. If tests had shown anything unsatisfactory, the electrician should have told you and explained what is needed.
Signs a quote is too cheap or too expensive
Signs it may be too cheap
- No mention of testing or an Electrical Installation Certificate
- No named make or model of consumer unit
- The electrician is not registered, or is vague about notifying the work
- Cash-only or large upfront payment demanded
- Pressure to accept the same day
- A price far below all the others, with no sensible explanation
A very low price usually means something has been left out, such as testing, paperwork, bonding or a proper unit.
Signs it may be too expensive
- A vague total with no breakdown
- Premium products you did not ask for
- Charges for extra work that testing has not shown to be necessary
- No explanation of why your job is more complicated than a standard replacement
- A price much higher than the local figures shown on this page, with no clear reason such as relocation or remedial work
If a quote seems out of line, ask the electrician to explain it line by line. A good one will be happy to. If you are still unsure, get another quote for the same scope.