Consumer Unit (Fuse Box) Replacement Cost in London: 2026 Guide
What you should expect to pay to replace an old fuse box in London, and why it is the most common fix after a failed EICR.
Updated · 5 min read · By the Polarity Electrics team
Typical London prices
A straightforward consumer unit swap in London usually costs between about £400 and £1,500, depending on property size, the number of circuits and whether you choose RCBOs. Our fixed price starts at £349 for a one-bed flat and scales by property size.
Signs your fuse box needs replacing
- Rewireable fuses with fuse wire
- No RCD protection, or a plastic unit under stairs
- Frequent tripping, buzzing or scorch marks
- An EICR recording C2 codes against the board
- Planned EV charger, extension or kitchen refit
RCBO or dual-RCD?
A dual-RCD board groups circuits under two RCDs, so one fault can trip half the house. An RCBO board protects each circuit individually — a fault on the kitchen sockets will not turn off your lights. RCBO boards cost more but are the better choice for most homes.
Certification
Consumer unit replacement is notifiable under Part P. A registered contractor notifies building control and issues an Electrical Installation Certificate — keep it for when you sell or re-let.
Frequently asked questions
How long does a consumer unit replacement take?
Half a day for most flats and a full day for larger houses.