EV Charging Cost Calculator UK: what does it cost to charge?

Electricity is sold in kilowatt-hours (kWh). The energy you add to the battery is the battery size multiplied by the share you charge. Multiply that by the price per kWh to get the cost. A 60 kWh battery charged from 20% to 80% adds 36 kWh, which at 26.32p per kWh costs £9.48.

Efficiency turns kWh into miles. At 3.59 miles per kWh, 36 kWh adds about 129.2 miles, and each mile costs 7.33p.

For a year of driving, the kWh used is the miles divided by the miles per kWh. The same miles in a petrol car use the miles divided by the MPG, times 4.54609 litres to a gallon, times the petrol price.

• Energy added (kWh) = battery size × (charge to − charge from) ÷ 100
• Cost of a charge = energy added × price per kWh
• Cost per mile = price per kWh ÷ miles per kWh
• Cost per year = miles per year ÷ miles per kWh × price per kWh

At 3.59 miles per kWh, charging at home at 26.32p per kWh costs 7.33p a mile. At the public charging average of 54.00p per kWh it costs 15.04p a mile. A petrol car doing 42.8 MPG at 159.9p a litre costs 16.98p a mile.

Over 8,000 miles that is £586.52 at home, £1,203.34 at public chargers and £1,358.73 in the petrol car. The table below shows the comparison.

Efficiency is miles per kWh. Your car's manual, the trip computer or the maker's website will show it, or kWh per 100 miles, in which case divide 100 by that number. We start from 3.59 miles per kWh, the average HMRC uses for electric cars (from Department for Transport data, weighted by company car sales). That is an average for company cars, not a figure for every driver, so use your own if you know it.

Battery size is the usable capacity in kWh, from the manual or the maker. The percentages are the levels the car shows.

The "Home" price is the Ofgem price cap average, 26.32p per kWh for 1 October 2026 to 31 December 2026 (Great Britain, Direct Debit, single-rate meter) (Ofgem). It is what many households pay on a standard tariff.

Some suppliers offer EV tariffs with a cheaper rate at certain times, usually overnight. If you have one, choose "My own price" and enter the rate for the time you charge. Your price will be different from the average.

The "Public charger" price is 54.00p per kWh. It is the average for slow and fast public chargers (under 50 kW) that HMRC uses in its advisory fuel rates from 1 September 2026, taken from the Zapmap price index (GOV.UK).

Rapid chargers (50 kW and above) are not in that average, and prices differ by network and by whether you are a member. For a rapid charger, choose "My own price" and enter the price shown at the charger.

The petrol car starts at 42.8 MPG, HMRC's average for a 1401 to 2000cc petrol car, and 159.9p a litre, the petrol price HMRC uses from 1 September 2026 (GOV.UK). HMRC's figures are weighted by company car sales. Change both under More options to match the car you would otherwise drive and what you pay.

Some energy is lost between the socket and the battery. If your car shows its efficiency measured at the battery, the energy you pay for is a little more than the battery gets, so your real cost is a little higher. Use an efficiency worked out from the wall, for example from a home meter, if you have one.

We do not show how long a charge takes. It depends on your car, the charger and how the speed slows as the battery fills, so any single figure would be a guess.

The result is an estimate. Prices change (the Ofgem price cap every three months, HMRC rates every three months), and real efficiency changes with speed, weather, load and how you drive.