How Much of a Litre of Petrol Is Tax? About 47% Right Now

Published 30 October 2026 · Updated 27 October 2026 · 2 min read · Petrol Prices Today team

When you pay 174p for a litre of petrol, nearly half of it is tax. Here is exactly how that works, using the national averages for the week commencing 26 October 2026: petrol 174.07p and diesel 199.22p a litre.

The two taxes on every litre

Fuel duty: a fixed 52.95p per litre on petrol and diesel.
VAT: 20% of the final price, which includes the duty. That is the same as one-sixth of the pump price.

The sum for petrol

VAT: 174.07p ÷ 6 = 29.0p
Duty: 52.95p
Total tax: 82.0p, which is 47% of the pump price

That leaves about 92p to cover the cost of the fuel itself, refining, shipping, the retailer's costs and profit.

The sum for diesel

VAT: 199.22p ÷ 6 = 33.2p
Duty: 52.95p
Total tax: 86.2p, which is 43% of the pump price

Diesel carries a lower tax share, but only because the fuel itself is so much dearer.

What this means for a full tank

On a 55-litre fill of petrol (about £95.74), roughly £45 is tax. On a diesel fill of the same size (about £109.57), around £47 is tax.

Why this matters when prices change

Because duty is fixed in pence, it does not shrink when oil prices fall. That is why a big drop in crude oil does not always bring pump prices down by much. It also means a duty change feeds through in full, plus VAT, as we explain in the Budget guide.

VAT works the other way: the higher the price, the more VAT the Treasury collects per litre.

What is in the rest of the price?

Roughly, the part of the price that is not tax covers:

the wholesale cost of petrol or diesel, which follows oil and refining markets
transport and storage
the retailer's operating costs and margin

The retailer's margin is the part you can influence, by choosing where to fill up. On the same day, we saw E10 prices in our database range from about 154p to 209p a litre. That 55p gap is far bigger than any change in tax.

Check the figures yourself

The duty rate is published by the government, and the national average prices come from weekly reports by motoring organisations. The detailed history is in our guide to fuel duty explained.

Find the cheapest fuel near you and pay as little of that margin as you can.