# E10 vs E5 petrol: which should you use?

E5 super unleaded costs 16.4p a litre more than standard E10 petrol in the UK right now — 189.7p against 173.3p. For almost every petrol car built since 2011, E10 is the correct fuel and the premium buys you nothing.

Last updated: 18 September 2026

## The difference

- **E10** — standard unleaded, up to 10% ethanol, 95 RON. The default UK grade since September 2021.
- **E5** — super unleaded, up to 5% ethanol, usually 97–99 RON. Sold as the premium grade.
The number after the E is the ethanol cap, not the octane rating.

## Current UK prices

| Grade | UK average | Forecourts |
| --- | --- | --- |
| E10 unleaded | 173.3p | 1471 |
| E5 super unleaded | 189.7p | 1092 |

Premium for E5: 16.4p a litre (£9.02 per 55-litre tank).

## Which grade does your car need?

Check the filler flap or handbook for a minimum octane rating.
- Says 95 RON → use E10. Super unleaded offers no benefit.
- Says 97 or 98 RON → use E5.
- Classic/pre-2000 vehicle, moped, garden or marine engine → use E5 unless confirmed E10-approved.

## Fuel economy

E10 gives roughly 1% lower mpg than E5 because ethanol is less energy dense. That is far smaller than the price premium, so E10 is cheaper per mile for most drivers.

## FAQ

### What is the difference between E10 and E5 petrol?

The number is the maximum percentage of renewable ethanol in the blend. E10 contains up to 10% ethanol and is the standard UK unleaded grade. E5 contains up to 5% and is sold as super unleaded, usually with a higher octane rating (97–99 RON against 95 RON for E10).

### Can my car use E10 petrol?

Virtually every petrol car built from 2011 onward is approved for E10, and most from the early 2000s are too. The main exceptions are some classic and vintage cars, a few early-2000s models, and some mopeds and garden machinery. The government publishes a vehicle checker, and your handbook or fuel filler flap will say.

### Is E5 super unleaded worth the extra money?

For a standard car, no. At the current 16.4p a litre premium you would pay about £9.02 more per 55-litre tank for fuel your engine is not tuned to exploit. It is worth it only if your handbook specifies a minimum of 97 or 98 RON — some performance and high-compression engines do.

### Does E10 reduce fuel economy?

Slightly. Ethanol carries less energy per litre than petrol, so E10 typically gives around 1% lower miles per gallon than E5. That difference is far smaller than the price premium on super unleaded, so E10 still works out cheaper per mile for most drivers.

### Does E10 damage engines?

Not in vehicles approved for it. Ethanol is more corrosive to some older rubber, plastic and untreated metal components, which is why pre-2000s and classic vehicles should stay on E5. In approved cars there is no issue with long-term use.


Canonical page: https://cheapestfuel.uk/fuel-prices/e10-vs-e5/
Live UK fuel price map: https://cheapestfuel.uk/map/
UK average prices: https://cheapestfuel.uk/how-much-is-petrol/

Prices are indicative. Always check the price displayed at the pump.