Petrol Cost Per Mile in the UK: Formula and Table

Petrol costs 24.7p a mile at 32 mpg. That uses the Department for Energy Security and Net Zero (DESNZ) average petrol price of 174.07p a litre for the week of 26 October 2026. To find your own figure, multiply the pence per litre by 4.54609 and divide by your miles per gallon.

How much does petrol cost per mile?

Petrol costs your car or van the pence-per-litre price multiplied by 4.54609, divided by its miles per gallon. The formula is:

Pence per mile = pence per litre x 4.54609 / mpg

British miles per gallon use the imperial gallon, which is 4.54609 litres. At 174.07p a litre, a gallon of petrol costs about £7.91. A vehicle that does 32 miles on that gallon pays 24.7p a mile.

Your mpg is the number that matters most, and the brochure figure is rarely the one you get. To measure it, fill up, note the odometer, drive normally, then fill up again and record the litres. Divide the miles by the litres and multiply by 4.54609. Repeat over several tanks.

DESNZ’s price includes fuel duty of 52.95p a litre and 20% VAT. If your business reclaims VAT on fuel, divide the pump price by 1.2 before using the formula, and keep the same basis every time so your figures compare.

What is the petrol cost per mile at different mpg?

At the week of 26 October 2026 price, petrol costs between 15.8p and 31.7p a mile across 50 to 25 mpg. The table uses DESNZ’s weekly road fuel prices: 174.07p a litre for that week, and 134.40p for the week of 27 October 2025.

Miles per gallon	Cost per mile, week of 26 Oct 2026	Cost per mile, week of 27 Oct 2025	Increase
25 mpg	31.7p	24.4p	7.3p
32 mpg	24.7p	19.1p	5.6p
40 mpg	19.8p	15.3p	4.5p
45 mpg	17.6p	13.6p	4.0p
50 mpg	15.8p	12.2p	3.6p

Source: DESNZ, weekly road fuel prices, petrol, UK average. Figures rounded to 0.1p.

For a rough sense of where cars sit, HMRC publishes the mean mpg it uses for company cars. For petrol that is 50.7 mpg for engines of 1,400cc or less, 42.8 for 1,401 to 2,000cc and 27.2 for over 2,000cc. At this week’s price those come to 15.6p, 18.5p and 29.1p a mile. HMRC’s advisory fuel rates guidance has the workings.

How has the petrol cost per mile changed in a year?

Petrol cost per mile has risen by about 30% in twelve months. DESNZ recorded 134.40p a litre in the week of 27 October 2025 and 174.07p in the week of 26 October 2026, a rise of 39.67p a litre. At 32 mpg that takes the cost from 19.1p to 24.7p a mile.

The path in between:

• Early 2026 low: 131.46p in the week of 9 February 2026, or 18.7p a mile at 32 mpg.
• Spring climb: from 132.14p in the week of 2 March 2026 to 158.17p in the week of 13 April 2026.
• Summer dip: 149.80p in the week of 6 July 2026, or 21.3p a mile at 32 mpg.
• Autumn high: 175.28p in the week of 12 October 2026, or 24.9p a mile at 32 mpg. That is the highest of the past year.

Petrol has not reached its record. DESNZ’s series, which starts in June 2003, peaks at 191.55p in the week of 4 July 2022. This week is 17.48p a litre below that.

A vehicle doing 20,000 miles a year at 32 mpg used about £3,820 of petrol at the price a year ago. At this week’s price the same miles cost about £4,950. That is around £1,130 more per vehicle for exactly the same driving.

Is petrol cheaper per mile than diesel?

At the same mpg, yes, because diesel is dearer per litre this week: 199.22p against 174.07p. In practice the gap is closed or reversed by miles per gallon, which differs vehicle by vehicle. At this week’s prices a diesel van at 36 mpg costs 25.2p a mile and a petrol van at 32 mpg costs 24.7p.

Compare like with like by using each vehicle’s own measured mpg. Do not assume one fuel wins. For the diesel calculation and the matching table, see diesel cost per mile.

How does speed change petrol cost per mile?

Speed changes it because fuel per mile rises as average speed climbs. The Department for Transport’s fuel consumption curves (TAG data book v2.03, May 2026) show a petrol van using 16.1% less fuel per mile at 60 mph than at 70 mph. A petrol car uses 8.9% less.

On a 24.7p-a-mile petrol van that is the gap between a fast motorway run and a steady one, and it applies to every mile driven at the higher speed. What speed costs per mile shows how to apply the percentage to your own figure.

Where can you see this week’s figure?

The live figure is on our fleet cost index, which updates every Tuesday after DESNZ publishes. It shows petrol, diesel and electric van cost per mile, with a fleet calculator and the weekly series back to June 2003. We also have a fleet fuel savings calculator for the saving from a speed cap.

For a cost per mile that covers more than fuel, use how to calculate fleet cost per mile. To compare against what HMRC lets you pay employees, see the advisory fuel rates.

Frequently Asked Questions

How much does petrol cost per mile in the UK?

It depends on your mpg. At 32 mpg petrol costs 24.7p a mile, using the DESNZ average of 174.07p a litre for the week of 26 October 2026. At 50 mpg it is 15.8p and at 25 mpg it is 31.7p.

How do I work out petrol cost per mile?

Multiply the price in pence per litre by 4.54609, then divide by your miles per gallon. For 174.07p a litre and 32 mpg that gives 24.7p. Measure your mpg over several tanks for a figure you can trust.

Why is my petrol cost per mile higher than the HMRC rate?

HMRC’s advisory fuel rates are reviewed quarterly and are based on an earlier fuel price. From 1 September 2026 the petrol rates are 14p, 17p and 27p a mile by engine size, and HMRC’s workings used 159.9p a litre. The pump price in the week of 26 October 2026 was 174.07p, so your actual cost can be higher.

How much has petrol cost per mile risen in a year?

At 32 mpg, from 19.1p in the week of 27 October 2025 to 24.7p in the week of 26 October 2026. That is 5.6p a mile, or about 30%, on DESNZ’s weekly petrol average.

Is a petrol van cheaper to run per mile than a diesel van?

Not necessarily. A petrol van at 32 mpg costs 24.7p a mile this week, and a diesel van at 36 mpg costs 25.2p. Which is cheaper depends on the real mpg of each vehicle.

Cut your fleet’s fuel bill

Your number is the figure in the table that matches your vehicle’s mpg. See this week’s cost on the fleet cost index, and put your own miles through the fleet fuel savings calculator.

A speed cap cuts the fastest, thirstiest miles. The Department for Transport’s fuel consumption curves (TAG data book v2.03, May 2026, source) show a petrol van uses 16.1% less fuel per mile at 60 mph than at 70 mph. What that is worth to your fleet depends on how many of your miles are driven above the cap.

AutoKontrol has made speed limiters in Britain since 1985, for vans, cars, HGVs and buses, installed nationwide: we come to you. To get your own saving worked out, book a free consultation or get a quote.