EV vs petrol vs diesel running costs UK

Which fuel is cheapest to run depends far more on how and where you drive than on the badge on the boot. An electric car driven modest miles and charged at home overnight is usually the cheapest. A diesel doing long motorway runs is often cheaper than an EV that has to rely on public rapid chargers. This page explains what actually drives the difference so you can work out your own case, rather than trusting somebody else’s average.

Every figure here changes with the energy market, the Budget and your own circumstances, so the page deliberately describes mechanisms rather than quoting numbers that would be wrong within months. Where you need a figure, the places to get a current one are named.

Fuel and charging: the biggest single difference

The gap between fuels comes down to pence per mile, and for an EV that number swings enormously depending on where you charge. Home charging on an off-peak overnight tariff is the cheapest way to move a car in the UK by a wide margin. Public rapid charging is the most expensive, and can cost more per mile than petrol.

That single variable decides most comparisons. An EV owner with a driveway and a cheap night rate is in a completely different position from a flat dweller relying on rapid chargers, even in the same car. Work out your own pence per mile from your actual tariff and your actual efficiency before believing any general claim.

For petrol and diesel, the equivalent lever is real-world consumption rather than the official figure, and diesel’s advantage grows with the proportion of steady, warmed-up motorway miles.

Road tax no longer separates them

This is where most older advice is now wrong. Zero-emission cars lost their VED exemption on 1 April 2025. Electric cars now pay the standard rate like petrol and diesel, and expensive ones can pick up the additional supplement too.

Anything you read that says EVs are road-tax free was written before that change. Our VED bands guide explains which system applies to which car, and the current amounts are on gov.uk.

For cars registered before April 2017 the CO2 band still does separate them, and an older diesel in a high band can cost several times what a small petrol costs. Check the band, not the fuel.

Insurance tends to run higher on EVs

Electric cars have generally attracted higher premiums than equivalent petrol or diesel models. The usual reasons given are repair complexity, battery replacement cost and a smaller pool of approved repairers, all of which push claims costs up.

The gap varies by model and by insurer far more than by fuel type in the abstract, and it has been narrowing as the repair network matures. The only figure worth having is a real quote for the specific car you are considering, on your own postcode and history. A general rule will not tell you anything useful here.

Servicing favours electric, but not by as much as people assume

An EV has no oil, no filters, no cambelt, no clutch and no exhaust, so routine servicing is genuinely simpler and there is less to go wrong on a schedule. That is a real saving and it recurs every year.

Two things offset it. EVs are heavy, so tyres wear faster and tyres are not cheap. And when something does fail it is more likely to be a specialist job at a franchised dealer rather than a local garage. The saving is real, it is just smaller than the “no moving parts” framing suggests.

Diesels carry their own specific risk: the particulate filter and the EGR system both dislike short urban journeys, and putting one of those right is one of the larger bills in ordinary motoring.

Depreciation is the cost nobody budgets for

For most owners, depreciation dwarfs fuel, tax, insurance and servicing put together, and it is the least predictable of the five. The used EV market has been volatile, moving with new-car pricing, battery technology and incentive changes in a way the petrol market has not.

Diesel carries its own risk here, from clean air zone expansion and the resale drag that comes with it. Petrol has been the steadiest, which is worth something in itself.

If you are choosing on cost, model depreciation before fuel. A car that holds its value badly will wipe out several years of cheap charging.

Battery health is the EV-specific unknown

A petrol engine’s condition shows up in service history and an MOT record. Battery degradation does not appear on either, and it is the single biggest factor in a used EV’s value and usability.

Ask for a state-of-health reading from a franchised dealer or an independent EV specialist before buying, and treat a seller who will not provide one as a warning. Manufacturer battery warranties typically run well beyond the standard vehicle warranty, so check what is left of it and whether it transfers.

How to work out your own answer

Take your genuine annual mileage. Split it honestly between short cold journeys and long warm ones. Price the electricity or fuel for that pattern at your own tariff. Get real insurance quotes on the two or three specific cars you are choosing between. Look up the VED band for each on gov.uk. Then compare.

That takes half an hour and gives you a number that applies to you, which is worth more than any national average. Before you buy, run the registration through the free check on this site for the tax status, the full MOT history and the mileage record on that specific car.