Premium vs Regular Fuel Calculator
Is premium fuel worth the extra cost for your car? Compare the annual price difference between standard and premium fuel, and see what efficiency gain you would need for premium to pay for itself.
UK average is roughly 7,400 miles per year.
How It Works
Enter your annual mileage, fuel efficiency, and the prices of both regular and premium fuel. The calculator estimates your annual fuel cost for each grade and shows you the extra cost of using premium. It also calculates the efficiency improvement that would be needed for premium to break even — so you can see whether the claimed benefits justify the price.
The Short Answer
For most UK drivers, premium fuel is not worth the extra cost. Independent tests show efficiency gains of just 1 to 3 percent, which translates to a saving of a few litres per year — nowhere near enough to offset the 15 to 20 pence per litre price premium. You would typically need a 13 to 14 percent efficiency improvement for premium to break even, and no credible test has shown anything close to that.
When Premium Might Help
- Older high-mileage engines — the cleaning additives in premium fuel can help restore injector performance after years of deposit build-up.
- Vehicles that tow or carry heavy loads — the higher cetane (diesel) or octane (petrol) can provide a small benefit under load.
- Cars that require 97+ RON — some performance cars are calibrated for higher octane fuel and may see reduced performance on E10.
For more detail, read our premium diesel guide and our E10 vs E5 petrol guide. To compare current prices in your area, use our price comparison tool.