Electric vs petrol cost calculator
Compare the total cost of owning an electric car and a petrol car, not just the fuel: depreciation, car tax, servicing and insurance too.
Over 4 years and 40,000 miles
The petrol car saves £2,020
| Cost | Petrol | Electric |
|---|---|---|
| Depreciation | £16,500 | £21,000 |
| Fuel or charging | £6,930 | £4,119 |
| Car tax | £1,055 | £1,387 |
| Servicing | £1,200 | £800 |
| Insurance | £2,400 | £2,800 |
| Total | £28,085 | £30,106 |
| Per mile | 70.2p | 75.3p |
The petrol price starts at the current UK average (today's UK average). Resale values, insurance and servicing are examples too: replace them with your own quotes for a fair comparison.
Running costs per mile
A petrol car doing 45mpg costs about 17.3p a mile in fuel at 171.5p a litre (today's UK average). An electric car doing 3.5 miles per kWh, charged at home on a 25p per kWh tariff, costs about 7.1p a mile. On a cheap overnight EV tariff it can be under 3p a mile; relying on rapid public chargers at around 75p per kWh raises it above 20p.
Car tax for electric cars
Since April 2025, electric cars pay car tax like any other car: £10 in the first year, then the standard rate, plus the expensive car supplement if the list price is over £50,000. The government has also announced a pay-per-mile charge for electric cars of 3p a mile from April 2028; it isn't law yet, so you can switch it off above. Work out car tax for any car.
What makes the biggest difference
- How you charge: home charging on an off-peak tariff is the single biggest saving.
- Depreciation: often the largest cost of all. Check real resale values for the models you're comparing.
- Mileage: the more you drive, the more the lower running costs of an electric car count.
Frequently asked questions
›Is an electric car cheaper to run than petrol?
Per mile, usually yes if you can charge at home. Whether it's cheaper overall depends mostly on the purchase price and how much value each car loses, which is why this calculator includes depreciation.
›How much does it cost to charge an electric car at home?
Multiply the battery size you're filling by your tariff. Adding 50kWh at 25p per kWh costs £12.50, enough for around 175 miles in a car that does 3.5 miles per kWh.
›Do electric cars pay road tax?
Yes, since April 2025: £10 in the first year and then the standard rate. A 3p a mile charge has been announced for April 2028.