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What you actually pay for in a litre of petrol: 47% is tax
Unleaded averages 173.9p a litre across Britain today. Of that, 52.95p is fuel duty and 29.0p is VAT. That leaves 91.9p to cover the crude oil, refining it, shipping it, the forecourt and its profit. Tax is 47% of what you hand over.
The split, per litre and per tank
| Where it goes | Unleaded | Diesel | Per 55-litre tank of unleaded |
|---|---|---|---|
| Fuel duty | 52.95p | 52.95p | £29.12 |
| VAT at 20% | 29.0p | 33.1p | £15.94 |
| The fuel, refining, delivery and the retailer | 91.9p | 112.7p | £50.56 |
| At the pump | 173.9p | 198.8p | £95.62 |
Why VAT is not 20% of the price
VAT is charged on the fuel and on the duty together, so it is one sixth of what you pay at the pump rather than a fifth of the cost before tax. You are paying 20% VAT on a 52.95p tax. That is the part most people have not noticed: the 52.95p of duty really costs you 63.5p by the time the VAT charged on top of it is counted, which is £34.95 of a 55-litre tank.
Duty is the same on petrol and diesel
Both carry 52.95p a litre. Diesel is dearer at the pump, averaging 198.8p against 173.9p, entirely because of what happens before tax: the untaxed portion is 112.7p for diesel against 91.9p for unleaded. The gap between the two pumps is a market difference, not a tax one.
The rate is scheduled to rise
The 52.95p rate is a temporary cut. On 2027-01-01 it is due to become 55.95p, a rise of 3p a litre, which is £1.65 on a 55-litre tank before the extra VAT on it. Our fuel duty guide works through the whole schedule and what each step costs.
The duty rate here is the only figure on this page that does not come from our own data. It is taken from HMRC's published schedule and was checked on 2026-09-25. Everything else is computed from the current prices when the site is built.
How this is measured
The pump prices are the mean across the 7,752 forecourts currently reporting unleaded E10 and the 7,850 reporting diesel B7. Forecourts whose prices have not moved in 14 days are left out, as are prices more than 25% from the national median, because one mistyped figure otherwise moves an average on its own. Data as at 2026-09-25.
Sources: the government Fuel Finder scheme for prices, which retailers are legally required to submit to, and HMRC for the duty rate. Figures are recalculated on every build.