Consumer unit replacement cost in 2026: what the price includes
In short: Replacing a consumer unit typically costs £450 to £700 in 2026 including the board, labour and the Electrical Installation Certificate, rising to £800 or more where the earthing and bonding need upgrading first. The job takes most of a day because every circuit must be tested and certified, not just reconnected.
A consumer unit swap is the most quoted job in domestic electrical work and the one where prices spread the widest. The board itself is a couple of hundred pounds. What the customer is actually buying is a day of methodical testing and a certificate that stands behind every circuit in the house, and that is where the price comes from.
Typical prices in 2026
| Job | Typical range |
|---|---|
| Straight swap, modern earthing, up to 10 ways | £450 to £600 |
| Larger property or split-load with SPD | £550 to £700 |
| Swap plus main bonding upgrade | £650 to £850 |
| Swap where rewiring faults surface under test | quoted after investigation |
Plus VAT where the firm is registered. London and the South East run 15 to 25 percent above these numbers, as with EICR pricing.
Why the earthing moves the price
The regs are blunt on this: you do not connect a new consumer unit to an installation whose earthing and bonding you have not verified. If the main protective bonding to the water and gas services is missing, undersized at 6mm where 10mm is needed, or the earthing conductor itself is inadequate, that work happens first. It is not upselling; energising a new board onto bad earthing puts the installer's signature on someone else's defect.
What surfaces under test
Old boards hide problems that only appear when every circuit is dead-tested. Borrowed neutrals between lighting circuits, insulation resistance dragged down by a forgotten junction box, a ring final that is not a ring. On most houses these are an hour of tracing; occasionally they are the start of a bigger conversation. A fair quote says up front how surprises will be handled rather than absorbing them silently into a price that punishes honest houses.
The paperwork that should follow
A consumer unit change is new work, so it gets an Electrical Installation Certificate, not a condition report, with a schedule of test results listing every circuit's Zs, insulation resistance and RCD times. In England and Wales the job is notifiable under Part P, so it is either registered through the electrician's scheme or via building control. If a quote is cheap because no certificate is included, the job is incomplete and it will surface at the next safety certificate or house sale.
Questions worth asking any quote
Does the price include the certificate and Part P notification? Is an SPD included, as current regs expect on most domestic boards? What happens if the bonding needs upgrading? An electrician who answers those three without hesitation is quoting the whole job. One who cannot is quoting a board swap and leaving the rest to chance.
Common questions
Why does a consumer unit replacement take a whole day?
Because the regs treat it as new work on every circuit it feeds. Each circuit gets dead tests, insulation resistance, polarity and earth loop readings before it goes back on, and those results have to appear on the schedule of test results with the certificate. The physical swap is the quick part.
Do I need a certificate for a new consumer unit?
Yes. A consumer unit change requires an Electrical Installation Certificate with a schedule of test results for every circuit, and in England and Wales it is notifiable under Part P, so the work must be registered with building control or done by a registered electrician who self-certifies.
Can a consumer unit be replaced without upgrading the bonding?
No competent electrician will energise a new board onto earthing and bonding that fails inspection. If the main bonding to water and gas is missing or undersized, that gets fixed first, which is why surveys before quoting matter.
SparkCerts runs the whole job for a UK sparky: quote it, fill the certificate in on site with readings checked as you type, and the invoice goes out with the cert attached. Three jobs free, then £12 a month.
Try it on your next job