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EV vs petrol running cost calculator
Compare what a year of driving costs in fuel for a petrol car against electricity for an electric car, with your own mileage and tariff.
Prices prefilled from the official Fuel Finder data, updated 28 August 2026. Change any box and the answer updates as you type.
The catch that decides it
The electricity price box is the whole story. Charge at home on an off peak electric car tariff at around 7p a unit and an electric car costs a fraction of petrol to run. Charge on a standard home rate of around 25p and it is still clearly cheaper. Rely on public rapid chargers at 80p a unit and it can cost more than petrol. So the honest answer to which is cheaper depends almost entirely on where you can charge.
The default of 25p is a typical standard home rate. Change it to your own tariff, or try 7p to see the off peak case and 80p to see the public rapid charging case. Our EV charging costs page has the current network prices.
What this does not include
This compares fuel and electricity only. It leaves out purchase price, depreciation, tax, servicing and insurance, which all differ between the two and can swing the overall picture. For the fuller running cost comparison with those assumptions spelled out, see our guide to what it costs to drive 100 miles.
Common questions
Is an electric car cheaper to run than petrol?
Usually yes, if you can charge at home. On an off peak tariff of around 7p a unit the electricity for a year's driving costs a fraction of the petrol. On public rapid chargers at around 80p a unit it can cost more than petrol, so where you charge decides it.
How many miles per kWh does an electric car do?
Most electric cars return between three and four miles per kWh in everyday driving, with small efficient models at the top of that range and large SUVs below it. Cold weather and motorway speeds reduce the figure.
Does this include the cost of buying the car?
No. It compares only fuel against electricity. Purchase price, depreciation, tax, servicing and insurance are left out, and they can change the overall comparison, so treat this as the running cost piece of the picture.