What it really costs to charge an electric car in the UK

The cost of charging an electric car in the UK is decided by where you plug in, not by which car you buy: on the DfT assumption of 3.5 miles per kWh, a mile costs 2.29p on an off-peak home tariff at 8 pence per unit, 7.46p at the Ofgem price cap rate of 26.11 pence for Great Britain, and 26.29p at a public rapid charger charging 92 pence, a spread of about 11.5 times, and at the top of that range a mile of electricity costs the same as a mile of petrol in a car returning 28 miles per gallon, so any petrol car more efficient than that is cheaper to fuel than that charger. Those are modelled figures, not a bill.

Home versus public, mile for mile

The arithmetic is simple enough to check by hand. Divide the price per unit of electricity by the miles the car travels on one unit, and you have the cost of a mile. At 3.5 miles per kWh, a car uses 0.286 units a mile, so a mile costs the unit price multiplied by that. The last column turns each figure back into petrol: it is the miles per gallon a petrol car would need to achieve to cost the same per mile, using the UK average pump price of 161.61 pence per litre for the week commencing 31 August 2026. That way no MPG has to be assumed for the comparison to hold.

Model, not a quote. Annual column assumes 8,900 miles a year — DfT National Travel Survey, England 2024 (self-estimated) — at 3.5 miles per kWh, which is 2,543 units of electricity. It counts electricity only: no standing charge, no vehicle tax, no insurance, no servicing, no depreciation. Nobody charges at one price all year, so a real bill sits between these rows.

What the Ofgem price cap actually caps

The cap limits what a supplier may charge per unit of electricity, and what it may charge as a daily standing charge, on a default or standard variable tariff. It does not cap your bill. Use more electricity and you pay more, without limit; the cap is a price control, not a spending ceiling.

Two further points are routinely misread. The headline figure is an average across the regional caps for England, Scotland and Wales, so the cap that applies where you live may be above or below it. And it is not a maximum anyone pays in the ordinary sense: fixed-price deals and dedicated EV tariffs are agreed outside the cap entirely, which is exactly why the off-peak rate in the table above can sit so far below it.

The standing charge is what you pay for being connected at all, every day, whether or not you charge a car. At the current rate that is £209 a year for electricity before a single unit is used, which is why it belongs in a household budget rather than in a per-mile figure.

Source: Ofgem energy price cap unit rates and standing charges. Basis in use on this page: Ofgem price cap, Direct Debit, Great Britain average, 1 Jul 2026 to 30 Sept 2026 — includes VAT at 5%.

The VAT trap

VAT is where most published charging comparisons quietly go wrong. Domestic electricity is charged at the reduced rate of 5 per cent. Electricity from a public charge point is standard-rated at 20 per cent. Same electrons, same car, different tax, and it applies on top of a commercial price that is already several times the domestic one.

On top of that, domestic electricity in Great Britain is temporarily zero-rated from 1 October 2026 to 31 March 2027. That temporary change is the reason two consecutive cap figures cannot be read as a trend.

The practical rule: never add VAT to a cap figure without checking which side of that window it sits on, and never chart the two periods as one line. The zero rate also does not reach public charging, which stays standard-rated throughout.

Northern Ireland is a different system

The Ofgem cap covers Great Britain, meaning England, Scotland and Wales. It does not apply in Northern Ireland, and neither does the temporary zero VAT rate. In Northern Ireland the Utility Regulator (UREGNI) approves Power NI’s regulated domestic tariff. That is an approval of a specific supplier’s tariff, not a cap and not a maximum tariff, and the two mechanisms should not be described in the same words.

• Regulator: Utility Regulator (UREGNI).
• Price-controlled domestic supplier: Power NI.
• Typical annual domestic bill for a credit customer: £1,093.
• VAT on domestic electricity stays at 5 per cent throughout the Great Britain zero-rate window.

Source: Utility Regulator. Ofgem’s price cap covers Great Britain only. In Northern Ireland the Utility Regulator approves Power NI’s regulated domestic tariff.

The driveway problem

Every cheap number on this page assumes a charger at home. A smart overnight tariff needs a smart meter, an eligible car or charger, and somewhere to park the car while it is plugged in. Many UK households have no off-street parking, and for them the off-peak rate is not a saving that is hard to reach: it is not reachable at all. Their realistic range starts at the public rows of the table.

We are not going to put a percentage on that group. Figures circulate widely, they disagree with each other, and we have not been able to verify one against a primary source, so the honest answer is that the size of the group is material but not something we can state. What matters for a buying decision is simpler: work out where you would actually charge before you assume any of these numbers apply to you. On-street charging, workplace charging and a friendly relative’s driveway all produce completely different arithmetic.

It also cuts the other way. A driver with a driveway and an off-peak tariff pays 2.29p a mile; a driver without one, charging at a peak-rate rapid charger, pays 26.29p. Over 8,900 miles that is £204 against £2,340 for the same car doing the same journeys.

Charging losses, and why two official efficiency figures disagree

Not all the electricity you buy reaches the battery. Some is lost in the charger, the cable and the car, and more of it goes to heating or cooling the battery in cold weather. You pay for what passes through the meter, not for what arrives in the cells, so any honest cost figure has to be measured at the wall.

The two official assumptions differ on exactly this point. DfT uses 3.5 miles per kWh for a 70 to 80 kWh battery and states that it includes charging losses. HMRC uses 3.59 for its advisory rate and does not say whether losses are included. Applied to the same cap rate, DfT’s figure gives 7.46p a mile and HMRC’s gives 7.27p, about 2.6 per cent apart on identical electricity, purely from the assumption used.

The percentage gap is fixed by the two assumptions, so it does not move with the electricity price; what grows with the price per unit is the gap in pence, and it is small on one mile and larger over a year. The rule we follow: state which assumption is in use, never mix one source’s efficiency figure with another’s price, and treat any resulting number as a model rather than as a bill. This page uses the DfT figure throughout, because it is the one measured on the side of the meter you pay for.

The HMRC Advisory Electricity Rate is not your cost

The Advisory Electricity Rate is an employer reimbursement rate. It sets what an employer may pay an employee per business mile in a company electric car, and what an employee may repay for private mileage, without a tax charge arising. It is a tax convention, not a measurement of what a private motorist spends.

• From 1 September 2026: 7p a mile for home charging and 15p a mile for public charging.
• Built on HMRC’s assumptions of 3.59 miles per kWh, 24.47 pence per unit at home and 54 pence per unit in public, the latter taken from a commercial charging price index.
• Reviewed on 1 March, 1 June, 1 September, 1 December.

Note that HMRC’s domestic input of 24.47 pence is not the cap rate of 26.11 pence in force now, which is another reason the advisory rate and your bill will not agree. If you drive a company car, the advisory rate is the number your employer works to. If you own the car, the rows in the table above describe your position and the advisory rate does not. HMRC advisory fuel rates.

Public charge points must show the price per unit

Under the Public Charge Point Regulations 2023, every public charge point in the UK must display its price in pence per kilowatt hour. That is what makes the comparison on this page possible at all, and it is the only figure worth comparing between operators: a session fee, a connection fee or a per-minute rate tells you nothing until it is converted back to a price per unit. Because these are commercial offers rather than regulated prices, they move without notice; the ones here were checked on 9 September 2026 and should be confirmed on the operator’s own page before you rely on them.

Why this matters more every year in the used market

Electric cars are no longer a rounding error in the used market. In 2025 there were 274,815 used battery electric transactions in the UK, a record 3.5 per cent share of all used-car sales, up from 2.5 per cent in 2024 (SMMT, published 10 February 2026). Most of those buyers are inheriting a car whose running cost was worked out by somebody else, on somebody else’s driveway, on a tariff they may not have.

So the useful question when you are looking at a used electric car is not “what does this car cost to charge” but “what will it cost to charge where I will charge it”. The car changes the miles per unit by a modest amount. Where you plug in changes the price per unit by a factor of about 11.5.

Work out your own figure

Where these figures come from

• Regulated electricity prices: Ofgem default-tariff cap, Direct Debit, Great Britain average of the regional caps. Verified 9 September 2026.
• Northern Ireland: Utility Regulator (UREGNI), Power NI regulated domestic tariff.
• Public and off-peak prices: operator and supplier published rates — commercial offers, not regulated prices — checked 9 September 2026.
• Efficiency: 3.5 miles per kWh, DfT. An assumption, applied consistently, not a measurement of any particular car.
• Petrol comparison: UK average pump price, week commencing 31 August 2026, from DESNZ weekly road fuel prices, converted at 4.54609 litres to the imperial gallon.
• Mileage used in the annual column: 8,900 miles — DfT National Travel Survey, England 2024 (self-estimated).
• Used market: SMMT used-car transactions, full year 2025, published 10 February 2026.