A consumer unit replacement typically costs £500–£1,200 in the UK, including the new consumer unit, installation, electrical testing and certification. For a straightforward replacement in a smaller property, costs may fall between £500 and £700. A larger home or an installation requiring a high-quality RCBO consumer unit may cost £700–£1,200 or more. In London, homeowners should generally budget around £550–£1,200, depending on the number of circuits, condition of the existing wiring and any faults discovered during testing. Current published UK estimates commonly range from approximately £400–£800 for standard replacements, while larger or more complex installations can reach £900–£1,200+.
Consumer Unit Replacement Cost Breakdown
Although every electrical installation is different, the following ranges provide a useful starting point:
| Type of replacement | Typical cost range |
|---|---|
| Small property with approximately 6–8 circuits | £500–£700 |
| Medium property with approximately 8–12 circuits | £600–£900 |
| Large property with 12–18+ circuits | £800–£1,200+ |
| Standard dual-RCD consumer unit | £500–£800 |
| Full RCBO consumer unit | £700–£1,200 |
| Consumer unit with surge protection | £650–£1,200 |
| Replacement involving minor remedial work | £700–£1,300 |
| Replacement involving extensive fault repairs | £1,000–£2,500+ |
| Commercial or multi-board installation | £1,000–£5,000+ |
These prices normally assume that the existing installation is reasonably accessible and that the wiring is in a safe enough condition to connect to the new consumer unit. Published UK pricing guides currently place a typical domestic replacement between approximately £440 and £750, with higher-specification RCBO installations frequently ranging from £800 to £1,200.
What Is a Consumer Unit?
A consumer unit is the main electrical distribution point in a property. It receives electricity from the incoming supply and distributes it across separate circuits for lighting, sockets, appliances, heating systems, outdoor equipment and other electrical installations.
The consumer unit contains protective devices designed to disconnect the electricity when a fault occurs. Depending on the age and type of the unit, these may include:
Miniature circuit breakers, commonly known as MCBs
Residual current devices, commonly known as RCDs
Residual current circuit breakers with overcurrent protection, known as RCBOs
Surge protection devices, known as SPDs
An arc fault detection device, known as an AFDD, where appropriate
Modern consumer units provide significantly more advanced protection than older fuse boxes fitted with rewireable fuses. The exact level of protection required will depend on the property, its circuits and the electrical design.
Consumer Unit Costs by Property Size
One-Bedroom Flat
Replacing a consumer unit in a one-bedroom flat usually costs around £500–£750.
A smaller flat may have approximately 4–8 circuits, covering lighting, sockets, an electric cooker, an immersion heater and possibly electric heating. The price may rise to £700–£1,000 where access is restricted, the meter cupboard is unusually small or faults are discovered.
Two-Bedroom Flat or Small House
For a two-bedroom property, expect a typical range of £550–£850.
These properties often have approximately 6–10 circuits. Adding surge protection, individual RCBO protection or upgrades to the earthing and bonding can increase the total to around £750–£1,100.
Three-Bedroom House
A three-bedroom house will generally cost between £650 and £1,000.
The property may have approximately 8–12 circuits, although extensions, electric showers, outdoor supplies and electric vehicle chargers can increase that number. Where several circuits require repairs, the project may cost £900–£1,500+.
Four- or Five-Bedroom House
A larger house may cost between £800 and £1,300 for a consumer unit replacement.
Properties with approximately 12–18+ circuits, multiple kitchens, garden buildings, electric heating, solar panels or electric vehicle charging equipment may need a larger board or more than one distribution board. In complex cases, costs can range from £1,200 to £2,500+.
Consumer Unit Costs by Type
Dual-RCD Consumer Unit
A dual-RCD consumer unit replacement normally costs around £500–£800.
This type of board divides several circuits between two RCDs. It can provide suitable protection, but a fault on one circuit may disconnect several other circuits sharing the same RCD.
For example, a fault affecting an outdoor socket could also interrupt power to indoor sockets or lighting, depending on the circuit arrangement.
RCBO Consumer Unit
A full RCBO consumer unit usually costs between £700 and £1,200.
Each circuit has its own RCBO, meaning a fault is more likely to affect only the circuit where the problem has occurred. This can improve fault isolation and reduce disruption elsewhere in the property.
The equipment cost is normally higher, but many property owners consider the additional £150–£400 worthwhile for greater circuit separation and convenience.
Consumer Unit With Surge Protection
A consumer unit incorporating surge protection may cost around £650–£1,200.
A surge protection device helps protect electrical and electronic equipment against transient overvoltages. The device itself may add approximately £50–£150 to the project, depending on the manufacturer, configuration and installation requirements.
Consumer Unit With AFDD Protection
Where arc fault detection devices are specified, the cost can rise to approximately £1,000–£2,500+.
AFDDs are more expensive than standard circuit breakers or RCBOs. The final price depends on how many circuits require this form of protection, with each device potentially adding around £100–£250+ to the material cost.
Commercial Consumer Unit or Distribution Board
Commercial distribution board replacements can range from £1,000 to £5,000+.
The price depends on the electrical load, number of circuits, phases, shutdown requirements and whether work must be completed outside normal operating hours. Large three-phase installations may cost £3,000–£10,000+, particularly where specialist switchgear is required.
What Is Included in the Price?
A professional consumer unit replacement quote will usually include some or all of the following:
The New Consumer Unit
The equipment may cost approximately £150–£500+, depending on:
The number of usable ways
The manufacturer
Whether the board uses MCBs, RCDs or RCBOs
Whether surge protection is included
Whether additional protective devices are required
A populated 10-way consumer unit may cost around £120–£250 before installation, although premium equipment and additional protection can push the material cost beyond £300–£500.
Electrician’s Labour
Labour for a standard replacement may range from £250 to £500.
Most straightforward replacements require approximately 4–8 hours, although testing, labelling and certification are also part of the job. London electrician day rates can be approximately £350–£500, compared with around £250–£350 in many other parts of the UK.
Electrical Testing
Testing may account for approximately £100–£300 of the total project cost.
Every circuit being connected to the new consumer unit must be tested. This helps establish whether the wiring is suitable and whether existing faults require correction.
A separate Electrical Installation Condition Report may cost around £100–£250, depending on the size and complexity of the installation.
Certification and Notification
Certification and applicable Building Regulations notification may be included in the quotation or listed separately at approximately £20–£100.
Consumer unit replacement is notifiable work under Part P of the Building Regulations in England. A suitably registered electrician can usually self-certify the work and arrange the required notification.
Disposal of the Old Unit
Removal and responsible disposal of the old consumer unit may cost approximately £50–£100 where it is not already included in the quotation. One published benchmark places consumer unit removal at around £75.
Factors That Affect Consumer Unit Replacement Cost
1. Number of Circuits
The number of circuits is one of the most important pricing factors.
A smaller installation with 6–8 circuits may cost £500–£700, while a property with 12–18 circuits may cost £800–£1,300+.
More circuits mean additional protective devices, more testing, more labelling and potentially a larger consumer unit.
2. Type of Protective Devices
A dual-RCD board may cost approximately £500–£800, while a full RCBO board may cost £700–£1,200.
Adding premium RCBOs, surge protection or AFDDs can increase the total by approximately £100–£1,000+, depending on the specification.
3. Condition of the Existing Wiring
A straightforward replacement assumes that the existing circuits pass the required tests.
Minor faults may add around £100–£400. Multiple damaged circuits, poor insulation resistance or unsafe alterations could add £500–£2,000+.
A consumer unit replacement does not automatically correct faults in the property’s wiring. Those faults may need to be repaired before the circuits can be safely energised.
4. Earthing and Bonding
The electrician will assess the earthing arrangement and protective bonding.
Minor upgrades may cost around £100–£300, while difficult bonding routes or more extensive earthing work may cost £300–£800+.
In some properties, access to gas or water services can make the work more time-consuming.
5. Meter Tails and Main Switch Arrangements
The meter tails connecting the electricity meter to the consumer unit may need upgrading.
Replacing or modifying the tails may add approximately £75–£250. Additional work involving the electricity supplier or network operator may result in charges of £100–£500+, depending on what is required.
6. Accessibility
A consumer unit installed in an accessible hallway cupboard is normally easier to replace than one located behind fixed furniture, in a cramped enclosure or near the ceiling.
Restricted access may add approximately £100–£400 in labour. Relocating the board can increase the cost by around £500–£2,000+, depending on the new cable routes.
7. Property Location
Labour rates vary by region.
A standard replacement outside major cities may cost around £500–£900. In London and parts of the South East, the same work may cost approximately £550–£1,200 because of higher labour, parking and operating costs.
Published London estimates currently place many consumer unit installations at approximately £502–£750, with larger or more complex projects extending beyond that range.
8. Parking and Congestion Charges
For properties in central or restricted parts of London, parking, congestion and travel expenses may add approximately £20–£150.
These charges should be stated clearly in the quotation or included within the total price.
9. Asbestos or Hazardous Materials
Some older fuse boxes or surrounding components may contain materials that require specialist assessment.
Testing may cost approximately £50–£150, while specialist removal could range from £200 to £1,000+, depending on the material and extent of the work.
10. Emergency or Out-of-Hours Work
A planned weekday replacement may cost £500–£1,200. Emergency, evening or weekend work may cost £750–£1,800+.
Out-of-hours rates can be around 25%–100% higher than standard daytime rates.
Common Additional Costs
The initial consumer unit quotation may increase if related electrical issues need attention.
| Additional work | Typical cost range |
|---|---|
| Minor circuit fault repair | £80–£250 |
| Multiple circuit fault repairs | £300–£1,500+ |
| Earthing or bonding upgrade | £100–£800 |
| Meter tail upgrade | £75–£250 |
| Main protective device changes | £100–£500+ |
| Moving the consumer unit | £500–£2,000+ |
| Installing a larger enclosure | £100–£400 |
| New circuit installation | £150–£800 per circuit |
| Electrical Installation Condition Report | £100–£250 |
| Partial rewiring | £1,000–£4,000+ |
| Full house rewiring | £4,000–£10,000+ |
For context, a full rewire of a typical three-bedroom house may range from approximately £4,450 to £8,000, depending on location, access and specification.
Why Can the Final Price Be Higher Than the Initial Estimate?
An electrician cannot always identify every concealed fault before disconnecting and testing the existing circuits.
For example, the initial quotation may be £700–£900, but testing could reveal:
A damaged cable requiring a £150–£500 repair
Inadequate bonding costing £100–£400
A faulty circuit requiring £100–£300 of investigation
Several unsafe alterations costing £300–£1,500+ to correct
A circuit requiring partial rewiring at £500–£2,000+
A clear quotation should explain what is included, what assumptions have been made and how unforeseen remedial work will be priced.
How Long Does Consumer Unit Replacement Take?
A standard consumer unit replacement usually takes around 4–8 hours.
A smaller, straightforward property may take approximately 4–6 hours. A larger installation with extensive testing may require 6–10 hours.
Where significant faults are found, work may extend across 1–3 days. Commercial installations may require 1–5+ days, depending on shutdown arrangements and the scale of the distribution system.
The electricity will usually need to remain off for several hours. Homeowners should plan for an interruption of around 4–8 hours, although the precise period will depend on the installation.
Do You Need an Electrical Inspection First?
An inspection before replacement may be recommended where the condition of the wiring is unknown.
A domestic Electrical Installation Condition Report generally costs around £100–£250, while larger properties may cost £200–£400+.
An inspection can help identify:
Damaged or deteriorated wiring
Inadequate earthing or bonding
Circuits likely to require repair
Signs of overheating
Incorrect alterations
Insulation resistance problems
Missing or inadequate protective measures
Although an inspection adds £100–£400 to the initial budget, it can reduce the risk of unexpected costs during the replacement.
Signs That Your Consumer Unit May Need Replacing
You should arrange an assessment if you notice any of the following:
The unit contains rewireable fuses
The enclosure is damaged or showing signs of heat
There is a burning smell
Protective devices trip repeatedly
Circuits are not clearly labelled
There is no RCD protection
The unit is overcrowded
Additional circuits cannot be safely accommodated
An inspection has identified defects
You are planning an extension, electric vehicle charger or major renovation
An older fuse box does not necessarily require immediate replacement solely because of its age. However, an assessment costing around £80–£250 can establish whether the existing equipment remains suitable and safe.
Where there is smoke, burning, crackling, visible heat damage or exposed live parts, isolate the supply only when it is safe to do so and contact an electrician urgently. Emergency attendance may cost approximately £100–£300, before any repairs are completed.
Is Consumer Unit Replacement a DIY Job?
Consumer unit replacement should not be treated as a DIY project.
The work involves the incoming electrical supply, protective devices, circuit testing, earthing arrangements and regulatory notification. Errors can create risks of electric shock, fire, equipment damage or circuits that fail to disconnect correctly during a fault.
A professionally completed domestic replacement generally costs £500–£1,200. Attempting to save the labour portion of approximately £250–£500 can lead to repair, inspection and certification costs of £500–£2,500+ where unsafe work must be corrected.
Using a registered electrician also provides the appropriate electrical certification and Building Regulations notification for applicable work.
How to Save Money on Consumer Unit Replacement
Arrange a Planned Replacement
Planned weekday work may cost around £500–£1,200, while an emergency or weekend replacement can cost £750–£1,800+.
Booking the work before the existing equipment fails can therefore save approximately £200–£600.
Request a Detailed Fixed Quotation
Ask for a quotation showing the cost of:
The consumer unit
Protective devices
Surge protection
Labour
Testing
Certification
Notification
Disposal
Potential remedial work
Comparing like-for-like quotes can prevent a low initial price of £400–£500 becoming a final bill of £900–£1,500 after necessary items are added.
Choose the Right Specification
The cheapest board is not always the best long-term choice.
A dual-RCD system may save around £150–£400 initially compared with a full RCBO installation. However, RCBO protection may offer better circuit separation and make future fault finding less disruptive.
Choose a specification based on the installation rather than automatically selecting either the lowest-priced or highest-priced equipment.
Combine Related Electrical Work
Completing related work during the same visit can reduce repeated call-out and travel costs.
For example, combining a consumer unit replacement with additional circuit work may save approximately £50–£200 compared with arranging several separate visits.
Make the Area Accessible
Clear cupboards, furniture and stored items before the electrician arrives.
Easy access may prevent approximately £50–£200 in avoidable labour costs, particularly where the consumer unit is inside a busy storage cupboard.
Provide Accurate Information
Tell the electrician about extensions, garden buildings, solar panels, battery storage, electric vehicle chargers, electric heating and previous electrical problems.
Accurate information reduces the chance that a quotation of £600–£800 later increases to £900–£1,300 because additional circuits or equipment were not disclosed.
Do Not Choose on Price Alone
A suspiciously low quotation may exclude testing, certification, notification, surge protection or fault repairs.
A complete quote of £650–£950 may offer better value than a headline price of £350–£500 that does not include essential parts of the work.
Questions to Ask Before Accepting a Quote
Before booking a replacement, ask:
Does the price include materials and labour?
Is electrical testing included?
Will I receive the correct electrical certificate?
Is Building Regulations notification included where required?
Does the unit include RCBO or RCD protection?
Is surge protection included?
How will additional faults be priced?
Is disposal of the old unit included?
Are parking and travel charges included?
What guarantee applies to the installation?
A professional quotation should provide a clear total range, such as £650–£900, while explaining which circumstances could increase the cost to £900–£1,300+.
Consumer Unit Replacement Cost FAQs
How much does it cost to replace an old fuse box?
Replacing an old fuse box typically costs between £500 and £1,200. A straightforward smaller installation may cost £500–£700, while a larger RCBO installation may cost £700–£1,200+.
How much is a consumer unit replacement in London?
In London, a typical domestic replacement costs around £550–£1,200. Larger properties, difficult access and extensive remedial work may increase the price to £1,200–£2,500+.
How much does an RCBO consumer unit cost?
A fully installed RCBO consumer unit generally costs between £700 and £1,200. Larger boards or installations requiring AFDDs may cost £1,000–£2,500+.
Can a consumer unit be replaced for £300–£400?
A price of £300–£400 may occasionally cover a very small or unusually straightforward job, but it is below many current all-inclusive market ranges. Check whether the quote includes the unit, protective devices, testing, certification, notification and VAT.
A more realistic complete budget for many homes is approximately £500–£1,200.
Does the replacement price include testing?
Testing is usually included in a professional quotation, but you should confirm this in writing. Testing may represent approximately £100–£300 of the project’s value.
Will the electrician need to rewire my house?
Not necessarily. Many consumer units can be replaced without rewiring.
Minor faults may cost £100–£500 to correct. Partial rewiring may cost £1,000–£4,000+, while a full rewire can cost approximately £4,000–£10,000+, depending on the property.
How often should a consumer unit be replaced?
There is no universal replacement interval of exactly 10, 20 or 30 years. The decision should be based on the condition, safety, suitability and test results of the installation.
Periodic inspection intervals commonly range from approximately 5–10 years, depending on the property type and circumstances.
Will replacing the consumer unit add value to my home?
A replacement may not add a fixed amount such as £1,000–£5,000 directly to the sale price. However, modern protection, clear certification and resolved defects can reduce concerns during surveys, conveyancing and negotiations.
Can I stay in the property while the work is completed?
Usually, yes. However, the electricity may be disconnected for approximately 4–8 hours. People working from home or relying on powered medical, security or accessibility equipment should make suitable arrangements in advance.
Get a Consumer Unit Replacement Quote From Route Electrical
For most London homes, a professional consumer unit replacement is likely to cost between £550 and £1,200, while larger or more complex projects may range from £1,200 to £2,500+. The only reliable way to establish the correct price is to assess the number of circuits, existing wiring, earthing, accessibility and required protective devices.
Route Electrical is a NAPIT-registered electrical company based in London, with more than 15 years of experience across domestic, commercial and industrial electrical work.
Whether you need to replace an outdated fuse box, upgrade to RCBO protection or investigate recurring electrical faults, Route Electrical can assess your electrical installation and provide a clear quotation based on the work required.
Contact Route Electrical on to request a consumer unit replacement quote in London.
