Why the same electric car can cost 2p or 23p a mile
Petrol prices vary by a few pence between forecourts. Electricity varies by a factor of ten between an overnight tariff at home and a motorway rapid charger. That single fact explains almost every argument about whether electric cars are cheap to run.
- Off-peak home charging is the cheapest motoring available in Britain by a wide margin — typically a small number of pence per mile. It requires off-street parking and a dedicated EV tariff.
- Standard-rate home charging is still comfortably cheaper than petrol, but the gap narrows a lot.
- Public rapid charging can cost about the same as petrol per mile, and sometimes more. If you cannot charge at home, the fuel-cost case for going electric largely disappears — the remaining arguments are servicing, refinement and emissions.
What this calculator does not include
Cost per mile is only one column of the ledger. Before switching, add:
- Depreciation. Historically the largest cost of any car, and the used-EV market has been volatile. See running costs.
- Insurance, which has often been higher for electric cars.
- Vehicle tax. Electric cars now pay the £200 standard rate, and the £40,000/£50,000 expensive-car supplement catches a lot of them.
- Home charger installation, a one-off cost of several hundred pounds.
- Servicing, which is genuinely lower on an electric car — no oil, no filters, no cambelt, and brake pads that last far longer thanks to regenerative braking.
If you have a driveway and an off-peak tariff, electric is dramatically cheaper per mile and stays cheaper even with a 3p pay-per-mile charge added. If you rely on public rapid chargers, run the numbers above before believing anyone’s headline — including ours.
Sources: pay-per-mile rates — PetrolPrices; VED rates — gov.uk. Default prices are indicative for late 2026 — replace them with what you actually pay. Last reviewed September 2026.