Cost to Replace a Consumer Unit (Fuse Box) in the UK
Typical UK prices for a new consumer unit, what affects the cost, how long the job takes and how to tell when your fuse box needs replacing.
The consumer unit, often still called the fuse box, is the control centre of your home's electrics. Replacing it is a common job when selling, renovating or after a failed condition report. The price depends on the size of the unit, the protection it offers and how easy it is to reach.
Typical costs
For a standard home with straightforward access, a consumer unit replacement typically falls somewhere around £400 to £900, including the unit, labour, testing and certification. Larger homes with many circuits, or work in London and the South East, can cost more. Treat this as a guide rather than a quote.
What is included
A proper replacement normally covers:
- Isolating the supply and removing the old unit.
- Fitting a new unit with suitable protective devices.
- Re-connecting and labelling each circuit.
- Testing every circuit.
- Issuing an electrical installation certificate or minor works certificate as appropriate.
- Notifying building control through the electrician's scheme where required.
Ask for the above in writing. If the quote does not mention testing and certification, ask why not.
What changes the price
- Number of ways. More circuits require a larger unit.
- RCD and surge protection. Higher specification units cost more, but offer broader protection.
- Condition of existing wiring. If testing reveals faults, these must be rectified before the unit can be certified, adding time and cost.
- Location. A unit in a cupboard under the stairs is easier than one in a cramped or awkward spot.
- Moving the unit. Relocating it requires extra cable and making good.
- Earthing and bonding. Older properties sometimes need these upgraded to meet current expectations.
When to replace
Signs your unit may be due for replacement include:
- Rewirable fuses or a unit made of brittle old plastic or wood.
- No RCD protection on socket circuits.
- Scorch marks, heat damage or a burning smell.
- Repeated nuisance tripping that testing cannot resolve.
- An EICR that recommends upgrading it.
- Plans for new circuits, such as an EV charger or electric shower, that the unit cannot support.
Not every old unit is dangerous, but an electrician is best placed to judge from the condition and the installation behind it. See what to check when a consumer unit trips for the common troubleshooting steps.
Is it a DIY job?
No. Replacing a consumer unit is notifiable work and involves the main incoming supply, which carries serious risk. It should be done by a registered electrician who can test and certify the result. Read which electrical work needs a registered electrician for the rules in plain terms.
What to expect on the day
You will typically lose power for several hours, so plan for charging devices, freezing food and resetting clocks. Make sure the electrician can reach the unit and the meter. Afterwards, ask them to show you which switch does what and keep the certificate with your house paperwork.
A worked example
A buyer is purchasing a 1980s three-bed house with an old rewirable fuse box and no RCD protection. A condition report flags the unit as unsatisfactory. An electrician quotes a replacement within the typical range for a 12-way unit, including testing and certification. On testing the circuits, they find one lighting circuit with poor insulation, which needs repair before the unit can be certified, adding a modest extra cost and some time. This is why many electricians quote a base price with a note that faults found on testing are extra. The worked figures are illustrative only.
Choosing between unit types
| Feature | What it does |
|---|---|
| Split-load unit | Separates circuits so one trip does not take out everything |
| RCBO unit | Individual protection for each circuit, so a fault only trips that one |
| Surge protection | Protects against some voltage spikes |
| Metal enclosure | Commonly used in homes to contain heat damage |
Ask the electrician to explain why they recommend a particular arrangement for your home.
A quote checklist
- Number of ways and spare ways.
- Type of protection on each circuit.
- Whether earthing and bonding will be checked and upgraded if needed.
- Testing and certification included.
- Making good around the unit.
- Allowance for any remedial work found.
Edge cases
- Rented homes: only the landlord should commission a replacement, and tenants should report concerns in writing.
- Flats: the meter and incoming supply may belong to the supplier or building, so access may need coordination.
- Smart meters or meter moves: the supplier or network operator handles these, separately from the electrician.
When to call a professional
Work on a consumer unit involves the main incoming supply and must be done by a registered electrician. Do not remove the cover or attempt to swap switches yourself.
Frequently asked questions
How long does a consumer unit replacement take?
Often a half to a full day for a straightforward home, depending on the number of circuits and any issues found during testing.
Do I need a new consumer unit for an EV charger?
Not always, but the existing unit must have capacity and suitable protection. An electrician will check this as part of the survey for a charger.
Do landlords need to replace old fuse boxes?
There is no blanket rule to replace every old unit, but landlords must keep the installation safe and inspected. A condition report will flag a unit that needs attention.
Will I lose power for the whole day?
Usually for a few hours. The electrician will isolate the supply, swap the unit, test, and restore power, so plan for chargers, freezers and anyone relying on powered medical equipment.