How to Compare UK Petrol and Diesel Prices Before a Drive

B& Business & Money Desk 2026-10-24 09:26 4 min read

Checking fuel prices near home, work or along your route can help you plan a drive’s fuel budget. RAC Fuel Watch publishes average UK petrol and diesel prices, but those figures are not quotes for individual forecourts. Use them as a broad benchmark, then check current prices at stations you might actually use before setting off.

A useful comparison has two parts: the price you will pay for the fuel you need, and the amount of fuel your journey is likely to use. A cheaper price per litre may make little difference to a small top-up, while a detour can use some of the fuel savings. The figures are estimates because both forecourt prices and real-world fuel consumption can change.

Use the national average as a benchmark

RAC Fuel Watch tracks average petrol and diesel prices across the United Kingdom. It can help you understand the wider market, but a national average cannot tell you what a specific station charges. Prices can differ between nearby forecourts, so use the average as a starting point for comparison rather than as the price to enter into a journey budget.

Compare like with like. Check regular unleaded against regular unleaded, and diesel against diesel. If your vehicle requires a particular grade, compare that grade rather than assuming a cheaper standard option is suitable. The useful figure for your budget is the price of fuel your vehicle can use at a station you can reasonably reach.

Check stations near your actual starting point

Search around the places you really travel from or to: home, work or the start of your planned route. Check a few stations and note the fuel type, displayed price and, where available, when the price was last updated. That timestamp matters because a listing may be old by the time you arrive, and the price can change.

Consider whether a station is open when you need it and whether it fits the route. A low displayed price may not help if reaching it means a long detour, extra time or relying on information that has not been checked recently. Before choosing, confirm the current price directly with the station or through a current local listing. If there is a delay before departure, check again.

Compare the saving with the extra driving

A difference in pence per litre is not the same as the amount saved on a fill. Multiply the price difference by the number of litres you expect to buy. For example, a 4p-per-litre difference on a 40-litre fill is £1.60 before accounting for extra driving.

Treat that as a simple comparison, not a guaranteed saving. You may buy less than 40 litres, the station price may change, and a detour uses fuel too. If the cheaper station is substantially out of the way or you only need a small amount, the total saving may be modest. Compare the likely fill against the journey to the station, rather than deciding on the per-litre figure alone.

Estimate journey fuel cost from your car’s economy

Use your vehicle’s real-world fuel economy rather than a general figure. If you track miles per gallon, divide the route distance in miles by your typical miles per UK gallon to estimate the gallons needed. Multiply the result by 4.546 to convert UK gallons to litres, then multiply those litres by the local price per litre you have checked.

If your vehicle reports consumption in litres per 100 kilometres, multiply the route distance in kilometres by that figure and divide by 100 to estimate litres used. Multiply the estimated litres by the checked price per litre. For a round trip, use the full return distance; for a one-way drive, use that leg’s distance.

Worked example

Suppose a round trip is 120 miles and your car typically returns 40 miles per UK gallon. Dividing 120 by 40 gives an estimate of 3 gallons. At 4.546 litres per UK gallon, that is about 13.6 litres. If the checked pump price is £1.50 per litre, the estimated fuel cost is about £20.40. Substitute your own route distance, typical economy and current local price to make the estimate useful for your drive.

These calculations estimate fuel use, not a fixed bill. Traffic, speed, weather, load, road type and driving style can all affect consumption. A journey estimate is most useful when the route and economy figure reflect how you actually drive.

Check the price and route before leaving

RAC Fuel Watch provides national context; a local station listing or direct check is needed for a forecourt price. Before you go, confirm that the price is current, the fuel grade matches your vehicle and the station fits your route. Recheck if your plans or departure time change, then use the checked local price and your car’s typical economy to estimate the journey fuel cost.

Source: RAC

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Source check Price check

RAC Fuel Watch provides UK average prices; local forecourt prices and journey costs should be checked for your own route and vehicle.

Checks

• Compare the same fuel grade
• Check the station price before departure
• Use your vehicle’s real-world fuel economy
• Include any detour in the comparison

Source

• RAC

RAC Fuel Watch Check UK fuel prices

Source

RAC Fuel Watch

Scope

United Kingdom

Updated

2026-10-24 09:26

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