EV vs Petrol Running Costs: The UK Driver's Guide

The single biggest factor: where you charge

Home charging and public charging are priced very differently in the UK, and this single factor often determines whether an EV is economically worthwhile for you.

Home charging on a standard tariff costs around 26.1p/kWh in mid-2026 (the Ofgem price cap rate for July–September). On a dedicated EV overnight tariff (like Octopus Go), this can fall to 7–10p/kWh during off-peak hours. At 26.1p/kWh and 3.5 miles/kWh, home charging costs about 7.5p per mile.

Public rapid chargingon networks like Pod Point, Osprey, or Gridserve typically costs 62–90p/kWh, averaging around 79p/kWh across UK networks in mid-2026. At that average, that's 22.6p per mile — more expensive than most petrol cars at current UK pump prices.

Petrol and diesel running costs

A petrol car doing 45 MPG at 153.5p/litre costs approximately 15.5p per mile in fuel. A diesel at 55 MPG and 168.6p/litre costs around 13.9p per mile.

Annual fuel costs for a 10,000-mile driver at these figures:

Note the reversal at 50% home charging: with public rapid charging now averaging 79p/kWh, an EV charged half the time on public networks costs more than diesel and about the same as petrol. Home charging access is what makes the EV case work in 2026.

Based on defaults: 10,000 mi/yr, 3.5 mi/kWh EV efficiency, 26.1p/kWh home, 79p/kWh public.

Real-world EV efficiency

Official WLTP efficiency figures for EVs, like official MPG for petrol cars, are measured under test conditions. Real-world efficiency is typically lower.

• →Small EVs (e.g. Fiat 500e, Renault Zoe): 3.5–4.5 miles/kWh real-world
• →Mid-range EVs (e.g. Tesla Model 3, Hyundai Ioniq 6): 3.0–4.0 miles/kWh
• →Large SUVs / performance EVs (e.g. Audi e-tron, BMW iX): 2.0–3.0 miles/kWh

Cold weather significantly reduces EV range and efficiency — factor in 15–25% lower efficiency in winter months, particularly at motorway speeds.

What this calculator still doesn't cover

The new full cost of ownership mode now includes purchase price, maintenance, VED / road tax, and a rough resale value estimate. There are still a few real-world costs and benefits that are left out because they vary too much by driver, location, or insurer:

• ⚠Insurance — depends heavily on the model, driver history, and insurer
• ⚠Home charger installation — the unit and fitting can add a meaningful upfront cost
• ⚠Finance costs — PCP, HP, lease deals, and APR all change the true monthly outlay
• ⚠Congestion charge, ULEZ, and workplace parking rules — these vary by location and employer
• ⚠Charging convenience and downtime — a home charger or workplace charger can change the experience even if the pounds-and-pence maths looks similar