What does an EV really cost to run? The whole bill.

This is the line that decides everything, so start here. An EV does about 3.4 miles per kWh, so 8,000 miles a year is 2,350kWh. Intelligent Octopus Gosells that between 11.30pm and 5.30am for 8p a kWh from 1 October 2026, which is £190 a year, or 2p a mile. On the Ofgem price cap, 26.32p a kWh from October to December 2026, the same year is £620, or 8p a mile. On the public network Zapmap's August 2026 average is 54p for slow and fast chargers and 77p for rapids, which is £1,270 and £1,810 a year, or 16p and 23p a mile.

A 45mpg petrol car at 172p a litre, the UK average for the week ending 21 September 2026, is about 17p a mile, or £1,390 for the same 8,000 miles. So the EV saves you £1,200 a year on fuel if you have a driveway and an EV tariff, £770 if you have a driveway and don't, and costs you £420 more if you live on rapids. Everything else on this page is smaller than that gap.

The two things that move it are the tariff and the driveway. The tariff guide ranks the off-peak rates; the home charging guide does the sums by battery size; and if you haven't got a driveway, that's a page of its own.

The free ride ended on 1 April 2025. A new EV now pays £10 for its first year and the standard rate, £200 a year from April 2026, after that. EVs registered between April 2017 and March 2025 pay the same £200; older ones, registered between 2001 and 2017, pay £20. A petrol car pays the same £200 standard rate, so on this line the two are level, and the first year is where a petrol car loses: a 111 to 130g/km petrol car pays £455 in year one against the EV's £10.

The catch is the expensive car supplement: £440 a year on top for 2026/27, for five years from the second year, on any car with a list price over £50,000 for an EV or £40,000 for petrol. Plenty of family EVs sit either side of that line, so check the list price of the exact spec before you sign, because £2,200 over five years is a real number. The road tax guide has the whole table.

You'll read that EVs are dearer to insure, and for a few years they were. The picture has moved. Confused.com's average comprehensive premium for March to May 2026 was £607 for an electric car, £733 for petrol and £732 for diesel. That's their customers, not the whole market, and it says as much about who buys EVs as about the cars, but it's the fairest single number I can find and it points the other way from the folklore.

The caveat: an EV that gets hit costs more to put right. Thatcham Research put electric claims at 25.5% dearer than petrol ones and 14% slower to repair in July 2023, and the gap has been closing since. Specialist parts, fewer trained body shops, and a battery pack worth thousands sitting under the floor. So a premium quote for the exact car matters more than any average, and a small EV with a modest list price is usually cheap to cover. Get the quote before the test drive, not after.

An EV has no oil, no filters to speak of, no clutch, no exhaust and no timing belt, and the brakes last for years because the motor does most of the slowing. So a service is mostly a look round, a pollen filter and a software check: about £165 a year on average in 2026, against about £205 for a petrol car. Some makers stretch the interval to two years, which halves that again.

Tyres are the one wear item that goes the other way. An EV is heavier and pulls harder from a standstill, so the driven tyres go every 20,000 to 25,000 miles rather than 30,000, at £80 to £150 a corner. Spread out, that's £50 to £100 a year more than a petrol car. Put the two together and the EV is still £40 to £80 a year cheaper on this line, which is nice, but it isn't what decides the sum.

This is the line that eats the fuel saving. Cox Automotive's figures for late 2025 put average EV depreciation at 38 to 42% after three years against 35 to 40% for petrol. The gap is a few points, but EVs cost more to start with, so the pounds are bigger: a £35,000 EV losing 40% is £14,000 gone in three years, about £4,700 a year, where a £28,000 petrol car losing 37% is £10,400, or £3,500 a year. That £1,200 a year is almost exactly the fuel saving.

Two things soften it. Used EV prices stopped falling in 2026: Auto Trader's index had them up 3.3% year on year in July, with three-to-five-year-old cars up 10.2%, so the worst is probably behind anyone buying now. And the spread between models is enormous. Some hold 70% of their value, some hold 30%, and the difference is mostly badge and battery health. Buy a car people want second-hand, or buy the second-hand one yourself and let someone else take the first hit.

Add the lines up for 8,000 miles a year. The EV, charged overnight on an EV tariff: £190 electricity, £200 tax, £607 insurance, £165 servicing and £4,700 lost value, about £5,860. The petrol car: £1,390 fuel, £200 tax, £733 insurance, £205 servicing and £3,500 lost value, about £6,030. The EV comes out under £200 ahead, and every pound of that comes from plugging in at home after midnight. That margin is smaller than the uncertainty in the lost-value line, which uses example list prices, so read it as level with a small edge to the EV rather than a win.

Move the charging and the answer moves with it. On the price cap the EV's electricity is £620 and the two cars are level. On public rapids it's £1,810 and the petrol car is £1,400 a year cheaper. Drive 15,000 miles instead of 8,000 and the home-charged EV pulls £2,000 clear, because the fuel saving scales and the depreciation doesn't. That's the whole answer: an EV is cheap to run when it's cheap to charge, and the rest of the bill is a wash.

The numbers above are for one petrol car and one EV. Yours will be different, which is the point of the cost calculator: it does these sums with your own car, your miles and your tariff. The steps below are the same sums with a pencil.