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Vehicles · Per journey

Fuel Cost per Journey Calculator

How much will that drive actually cost in fuel? Plug in miles, MPG and pump price.

mi
mpg
£ /L

Fuel cost for journey

£36.62

0p15 per mile

Fuel needed25.3 L (5.56 gal)
Cost per mile14.6p
Round trip cost£73.24

How we calculated your result

Gallons = miles ÷ MPG. UK MPG is imperial gallons (4.546 L). Cost = litres × pump price. Cost-per-mile lets you compare against HMRC’s 45p/mile mileage allowance.

Official UK rules in simple English

  • HMRC AMAP rate: 45p/mile for first 10,000 business miles.
  • Advisory Fuel Rates (AFR) published quarterly for company-car drivers.
  • UK uses imperial gallons (4.54609 L), not US gallons (3.785 L).

Common pitfalls to watch out for

  • ⚠ Manufacturer MPG is optimistic

    Real-world MPG is typically 20–30% lower than WLTP figures. Use historical fill-up data.

  • ⚠ Motorway vs town

    City driving can halve MPG on a small petrol — adjust if mostly stop-start.

  • ⚠ AFR vs AMAP confusion

    AMAP is for using your own car for work (45p). AFR is for fuel reimbursement on company cars (much lower).

Frequently asked questions

What price per litre to use?
Check Petrol Prices UK or your local supermarket. UK average ~145p petrol / 155p diesel mid-2025.
Why imperial gallons?
UK historical convention. MPG figures on adverts are always imperial.

Educational. Estimates only — actual fuel consumption varies.

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