What Is E10 Petrol?

E10 at the pump: what you need to know

E10 is the UK’s standard petrol at 95 octane, introduced across Great Britain in September 2021 and extended to Northern Ireland in November 2022. At its simplest, E10 is regular petrol blended with up to 10% renewable ethanol. That ethanol typically comes from crops such as wheat or sugar beet, including UK-grown feedstocks. By increasing the renewable portion, E10 helps reduce overall carbon emissions compared with the older E5 blend.

For most drivers, the switch is straightforward. Modern petrol engines were designed with these blends in mind and UK fuel includes additives that help protect against corrosion. As a result, vehicles from 2002 onwards are generally fine on E10 without modification. Where your car is older, or if you run a cherished classic, E5 remains available at many pumps as super unleaded, typically 97 octane or higher.

You may notice a small change in fuel economy. Ethanol carries slightly less energy than pure petrol, so some vehicles see around a 3% drop in miles per gallon. In everyday terms, that is often within the normal week-to-week variation drivers already experience from traffic, weather and tyre pressures. You might also find octane ratings are a touch higher on premium fuels, which some performance engines prefer.

What does this mean at the forecourt today? In most stations that offer two petrol grades, the green-labelled standard nozzle is E10, while the premium nozzle dispenses E5 super unleaded. A few rural or small sites stock only one grade, so planning ahead helps if you need E5 for compatibility. Ultimately, E10’s appeal is practical as well as environmental: a familiar fuel with a measurable emissions benefit, available nearly everywhere in the UK.

Knowing your car’s compatibility is the quickest way to refuel with confidence.

Bottom line: E10 is now the UK’s default petrol. If your vehicle is post-2002, it is likely good to go.

Is this right for you?

If you drive a petrol car built from 2002 onwards, E10 will usually be the sensible, cost-effective choice for daily motoring. It offers broad availability, helps cut tailpipe CO2 compared with traditional petrol and should not require any changes to how you fill up. Motorcyclists and light van drivers typically see the same benefits and considerations.

Owners of classic or pre-2000 vehicles should approach E10 with care. Ethanol is hygroscopic and can act as a solvent, which may accelerate wear in older rubber seals, hoses and gaskets. In those cases, E5 super unleaded is the safer routine fuel, with specialist advice recommended if you plan to convert components for E10 use.

Your refuelling choices today

1. E10 regular unleaded (95 RON) - standard petrol at most UK pumps, up to 10% ethanol, lower CO2 than E5.

2. E5 super unleaded (97+ RON) - premium fuel for older or high-performance engines, typically lower ethanol content.

3. Use E10 and monitor MPG - track consumption over a month to understand any change.

4. Choose E5 for classics - avoid potential material degradation in older systems.

5. Mix in an emergency - small top-ups of the other grade are generally acceptable, then revert to your usual fuel next fill.

What it means for your wallet and the road

Vehicle compatibility and practicalities

In the UK, E10 is considered safe for the vast majority of petrol cars and motorbikes registered from 2002 onwards. That confidence stems from modern fuel system materials and the fact that E10 has been the reference fuel for emissions testing of new cars for years. UK suppliers also blend corrosion inhibitors to manage ethanol’s moisture-absorbing tendency, helping keep injectors, pumps and lines in good order.

Older vehicles are a different story. Ethanol can loosen historic deposits and may degrade legacy rubbers, plastics and sealants used in pre-2000 fuel systems. If you run a classic, use E5 super unleaded and consult marque specialists before making any changes. For occasional use vehicles, refresh fuel more frequently and store them with care to minimise moisture ingress.

Availability is straightforward: most multi-grade stations offer E10 at 95 octane and E5 at 97 or higher. A minority of small or rural forecourts may carry just one grade, so plan routes if you must use E5. If you are considering upgrading to a newer, E10-ready car, Kandoo can help you explore finance options through its panel of lenders to match your budget.

Refuel with confidence: step by step

1. Check your vehicle’s handbook or manufacturer guidance.

2. Confirm the pump label shows E10 or E5 correctly.

3. Choose 95 RON E10 unless your car requires premium.

4. Fill steadily and avoid brim-filling after the first click.

5. Keep receipts and note mileage for MPG tracking.

6. Drive normally and monitor performance for a few weeks.

7. If issues arise, revert to E5 and seek advice.

What to weigh up

Before you choose at the nozzle

A little preparation goes a long way. Confirm your car’s compatibility and decide whether you value octane, cost, or simplicity most. Expect small MPG variations with E10 and remember that driving style, tyre pressures and winter temperatures often shift consumption more than fuel choice alone. If your car is older, consider the long-term health of seals and hoses before experimenting, and keep an eye on starting, idling and fuel lines after any change.

If you do mix fuels occasionally, there is no need to drain the tank. Just return to your preferred grade at the next fill. Store fuel safely and avoid long periods with a near-empty tank, which can invite moisture. Above all, use evidence: track your spend and mileage for a month so you can make a calm, data-led decision.

Alternatives if E10 is not ideal

1. Use E5 super unleaded consistently for older or performance vehicles.

2. Upgrade fuel system components to ethanol-resistant materials where appropriate.

3. Consider a newer, E10-optimised car if you drive frequently.

4. Explore hybrid or electric vehicles to reduce fuel dependence.

5. Reduce car use with car-sharing, cycling or public transport where practical.

Frequently asked questions

Q: What exactly is in E10 petrol? A: It is standard petrol blended with up to 10% renewable ethanol, typically from crops such as wheat or sugar beet, designed to cut overall CO2 emissions.

Q: Will E10 damage my engine? A: For most post-2002 vehicles, no. UK E10 includes protective additives and modern components are designed for it. Older or classic cars may be better on E5.

Q: How much fuel economy could I lose? A: Expect around a 3% reduction in some vehicles. Many drivers will see little real-world change once normal traffic and weather variation is considered.

Q: Is E5 still available in the UK? A: Yes. At stations with two petrol grades, E10 is the 95 octane standard, while E5 remains as super unleaded at 97 octane or higher.

Q: Can I mix E10 and E5? A: Mixing small amounts is generally fine. Simply return to your usual grade at the next fill and monitor performance as normal.

Q: Does ethanol cause moisture problems? A: Ethanol is hygroscopic, but UK fuels contain inhibitors to manage moisture. Good storage practices and regular use help keep systems healthy.

How Kandoo can help

Thinking about upgrading to a newer, E10-ready car or moving to a more efficient model? Kandoo is a UK-based retail finance broker that connects you with a wide panel of lenders, helping you compare options and secure a competitive rate to suit your monthly budget, all with clear terms and no fuss.

Important information

This guide provides general information for UK motorists and is not mechanical advice. Always follow your manufacturer’s guidance and consult a qualified technician for older or modified vehicles. Fuel pricing and availability can vary by region and station.