Fuel Duty Calculator 2025/26

Understanding UK Fuel Duty

Fuel duty is an excise duty charged by HMRC on fuel used for road vehicles in the United Kingdom. It is one of the largest single sources of government revenue from motoring, raising around £25 billion annually. The duty is levied at a flat rate per unit of fuel regardless of the fuel's price on world markets, which means that as crude oil becomes cheaper, the tax makes up a higher proportion of what you pay at the pump.

The key distinction with fuel duty is that it is charged before VAT. VAT at 20% is then applied to the entire pump price — which already includes the fuel duty element. This means motorists effectively pay tax on a tax. At a typical pump price of around 145p per litre for unleaded petrol, approximately 52.95p is fuel duty and a further 24p or so is VAT, meaning total taxation is roughly 77p — around 53% of the pump price. The remaining 68p covers the wholesale fuel cost, distribution, and the retailer's margin.

The government has frozen fuel duty at 52.95p per litre since March 2022, having previously cut it from 57.95p per litre. This freeze has been repeatedly extended through successive Budget statements.

Different Fuel Types and Their Duty Rates

Not all fuels are taxed at the same rate. The standard road fuel rate applies to most petrol and diesel, but specialist fuels attract either lower rates (to encourage alternative fuel use or for off-road purposes) or different assessment bases.

Red Diesel and the 2022 Rule Change

Red diesel attracted substantial reform in April 2022. Before that date, a wide range of off-road users — including construction, mining, and many commercial sectors — were entitled to use the lower-rate fuel. HMRC significantly narrowed the entitlement, restricting it broadly to agriculture, horticulture, fish farming, heating of non-commercial premises, and a few other specific uses. Most construction machinery, commercial refrigeration units, and off-road plant now must use full-rate fuel.

The lower rate of 11.14p per litre represents a substantial saving per litre compared to road fuel duty. For qualifying farmers operating heavy machinery across many hours, the annual difference can be tens of thousands of pounds. HMRC has powers to check fuel used in vehicles and machinery, and using red diesel illegally can result in significant penalties and vehicle seizure.

How VAT Interacts with Fuel Duty

VAT on fuel is charged at the standard rate of 20% on the whole pump price. Because fuel duty is already embedded in the pump price before VAT is applied, the effective tax on the duty component alone is 20% of 52.95p — about 10.6p — in addition to the duty itself. This is sometimes described informally as "tax on a tax."

For VAT-registered businesses using fuel for business purposes, the VAT element may be reclaimable subject to HMRC's fuel scale charge rules if the vehicle has any private use. Pure business-only use (such as some fleet or commercial vehicles) can allow full VAT reclaim on fuel. The fuel duty element is never separately reclaimable and is simply a cost of operating road vehicles.

At home heating oil rates, domestic users pay no VAT on heating oil at all (rated at 5% for domestic use), and the excise duty rate is the substantially lower red diesel rate. This makes heating oil considerably cheaper per unit of energy than road diesel.

Annual Fuel Duty Cost for Typical Drivers

For a typical UK car driver covering around 7,400 miles per year (the current UK average) at a fuel economy of 35 mpg, annual petrol consumption is roughly 960 litres. At 52.95p per litre duty, that represents around £508 in fuel duty alone, before VAT. A driver covering 15,000 miles annually would pay around £1,030 in fuel duty at the same fuel economy.

These figures help illustrate why fuel duty is a significant household cost. They also explain the political sensitivity around changes to the freeze — any increase would immediately and visibly affect household budgets at the pump.