With petrol at roughly 151p/litre and diesel 167p/litre in mid-2026, diesel still wins on cost-per-mile for high-mileage motorway drivers thanks to better economy, while petrol suits average or lower-mileage/urban use. Hybrids typically cost 10-20% less to fuel than an equivalent petrol car in town driving. Electric cars are the cheapest to run per mile if you can charge at home overnight, but public rapid charging can cost more per mile than petrol, and EVs pay less Vehicle Excise Duty than combustion cars from April 2025 onward (all cars now pay some VED, including EVs).
At a glance
| Fuel type | Best suited to |
|---|---|
| Petrol | Average/lower mileage, urban and mixed driving |
| Diesel | High-mileage motorway drivers, towing |
| Hybrid (HEV/PHEV) | Urban/mixed driving wanting lower fuel bills without home charging |
| Electric (BEV) | Drivers with home or workplace charging access, low BIK for company cars |
Petrol: the flexible default
Petrol engines are cheaper to buy, service and repair than diesel or hybrid systems, and petrol at around 151p/litre suits drivers who don't cover big annual mileage — the fuel-economy gap to diesel narrows or disappears once you factor in diesel's often-higher purchase price and exhaust after-treatment costs (AdBlue, particulate filters). Petrol is also the simplest choice for occasional or short-journey driving, since diesel particulate filters and hybrid batteries both perform best with regular longer runs.
Diesel: still relevant for high-mileage drivers
Diesel remains more fuel-efficient per litre than petrol, and at motorway speeds that gap widens. For drivers regularly covering 15,000+ miles a year, especially motorway-heavy, the better economy can offset diesel's roughly 16p/litre premium over petrol (167p vs 151p in mid-2026). Diesel's downsides are real, though: diesel particulate filters can clog on cars used mostly for short trips, AdBlue needs regular topping up on newer diesels, and many city Clean Air Zones and ULEZ schemes charge older diesels that don't meet Euro 6 emissions standards.
Hybrids: a middle ground without charging infrastructure
Full hybrids (HEVs) use a small battery and electric motor to assist the engine, particularly in stop-start town driving, typically cutting fuel use by 10-20% versus an equivalent petrol car without ever needing to be plugged in. Plug-in hybrids (PHEVs) add a bigger battery for 20-40 miles of pure-electric range — genuinely cheap if you charge overnight and do short daily journeys, but if never charged, a PHEV can be less efficient than a regular hybrid because it's hauling a heavier, larger battery around.
Electric: cheapest per mile with home charging
Charging at home overnight on a cheap electricity tariff typically costs the equivalent of 3-6p per mile — a fraction of petrol or diesel's 15-20p+ per mile. But rely solely on public rapid/ultra-rapid chargers and the cost per mile can rise close to, or even above, petrol, since public rapid charging is priced well above domestic electricity rates. Electric cars also carry the lowest company car Benefit-in-Kind tax band in the UK — 4% for 2026/27, rising gradually to a 9% cap by 2029/30, versus up to 37% for the highest-emission petrol/diesel cars.
Running cost snapshot
| Fuel type | Typical cost per mile (fuel only) | VED band |
|---|---|---|
| Petrol | ~13-17p | Based on CO2 at first registration, then standard rate |
| Diesel | ~13-16p (better on motorway) | Based on CO2 at first registration, then standard rate |
| Hybrid | ~10-14p | Small discount vs petrol/diesel equivalent in year one |
| Electric (home charging) | ~3-6p | Lower rate than combustion, though EVs now pay VED |
Don't choose diesel purely for economy if most of your driving is short urban trips — infrequent long runs can let the particulate filter clog, leading to expensive repairs that erase any fuel savings.
Frequently asked questions
Is diesel or petrol cheaper to run in the UK?
Are hybrids worth it if I can't charge at home?
Is an electric car cheaper to run than petrol?
Do electric cars pay road tax in the UK?
What's the Benefit-in-Kind rate for an electric company car in 2026/27?
Sources & further reading
- RAC — Latest UK petrol and diesel prices
- gov.uk — Vehicle tax rate tables
- gov.uk — Expenses and benefits: company cars (BIK)
Figures, prices and policy details were current at the last-updated date above. Automotive pricing, incentives and regulations change frequently — verify time-sensitive details with the linked primary sources. Read our editorial policy and fact-checking standards.
