The short answer
An EV charger circuit requires a dedicated, protected circuit in your consumer unit, typically on a 32A or 40A RCBO. If your existing consumer unit has a spare way and suitable capacity, the charger can often be added to it without a board replacement, with the charger installation cost covering the new circuit. If the board is full, outdated or lacks suitable protection, a new consumer unit is needed: a consumer unit replacement alongside EV charger installation typically adds £350–£800 to the charger cost, depending on board type and property. Combined jobs — charger plus new board — commonly run £800–£1,800 in total, though wide variation exists. All EV charger installations in the UK must meet BS 7671 and the OZEV/UKAS requirements for the relevant OLEV grant scheme (where applicable), and the circuit work is notifiable under Part P.
The question of whether you need a new consumer unit for your EV charger depends entirely on the state of your existing board. Many homes can have the charger circuit added to a sound, modern board without a full replacement; others cannot. Here is how to tell which applies and what the costs look like.
Typical EV charger board costs
- New circuit only (board has spare way)included in charger install quote
- Consumer unit upgrade (if needed)~£350–£800 additional
- Combined charger + new board (typical)~£800–£1,800 total
- RegulationPart P notifiable; registered electrician required
- EV charger grantOZEV grant available — check eligibility
When your existing consumer unit is sufficient
Most modern consumer units — a unit fitted in roughly the last 15 years with RCD or RCBO protection and at least one spare way — can accommodate an EV charger circuit without a board replacement. The charger installer will:
- Identify a suitable spare circuit position in the board.
- Fit a 32A or 40A RCBO (if not already present) to provide the dedicated protection the charger circuit requires.
- Run a cable from the board to the charger location.
In this case, the consumer unit cost is a single RCBO device (typically a small fraction of the total job) and there is no full board replacement. The total charger installation cost in this scenario commonly runs £800–£1,200 including the charger unit and installation, though prices vary by charger brand and cable run length.
When a new consumer unit is needed
A full consumer unit replacement alongside the EV charger installation becomes necessary when:
- The existing board is full with no spare ways and cannot be extended.
- The board uses old rewireable fuses or lacks the RCD protection needed to safely add a high-current circuit.
- The board is damaged, overheating or has existing faults that testing flags before the new circuit can be certified.
- The board's incoming supply capacity is insufficient — older properties with a 60A or 80A cut-out may need a supply upgrade before a 7kW or 11kW charger can safely be added, which requires DNO (distribution network operator) involvement.
When a new board is needed, the two jobs are usually quoted and done together, which is more efficient than doing them separately.
| Scenario | Typical total cost | Notes |
|---|---|---|
| EV charger only (board has spare way) | £800–£1,200 | Includes charger unit, circuit, fitting |
| EV charger + new RCD consumer unit | £1,000–£1,600 | Board replacement added to charger job |
| EV charger + full RCBO consumer unit | £1,200–£1,800+ | RCBO board, full replacement |
| Supply upgrade required (DNO involvement) | Variable; days to weeks to arrange | Required if incoming fuse is undersized |
| Garage install + charger + new board | £1,200–£2,000+ | Depends on cable run and scope |
Indicative UK figures for guidance. Sources: Checkatrade EV charger cost guide; MyJobQuote fuse box cost guide. Actual costs depend on property, installer and scope.
Grants and installer requirements
The OZEV Electric Vehicle Homecharge Scheme (EVHS) provides a grant of up to £350 towards the cost of installing a home EV charger for eligible applicants (eligible vehicle owners living in rental accommodation as of 2023 rules; owner-occupiers in houses were removed from the scheme). The EV chargepoint grant for renters and flat owners scheme has its own eligibility rules which change periodically — check gov.uk for current terms.
Regardless of grant eligibility, all EV charger installations must be carried out by an OZEV-registered installer, which also means they must be a registered electrician completing the work to BS 7671 and notifying under Part P. The consumer unit work is part of the same notifiable installation.
Frequently asked questions
Do I need a new consumer unit for an EV charger?
Not necessarily. If your existing consumer unit is modern, has RCD or RCBO protection and has at least one spare way, the EV charger circuit can usually be added to it. A new board is needed if the existing one is full, outdated, uses old rewireable fuses or has faults that need fixing before the circuit can be certified.
What size circuit does an EV charger need?
A standard home EV charger (7kW) typically requires a dedicated 32A or 40A circuit with its own RCBO. The exact rating depends on the charger model and the installer's assessment. This circuit must not share its protection with other loads.
Can I claim a grant for the consumer unit if I need to replace it for an EV charger?
The OZEV grant (where you are eligible) applies to the charger installation, not to a consumer unit replacement. If the board needs replacing as part of the job, that cost is separate from the grant and is met by the owner. Check current gov.uk OZEV scheme terms, as grant eligibility and amounts change.
Sources & further reading
- Checkatrade — EV charger installation cost guide
- gov.uk — EV chargepoint grant for homeowners
- Electrical Safety First — consumer unit best practice guide
Figures on this page are typical UK ranges drawn from published sources and depend on your specific property and installation. They are guidance, not a quotation.