Running the business
HMRC simplified mileage allowance (cars and vans)
- where
- mileage allowance (£)
- rate for the first band (p/mile)
- business miles in the tax year
- miles in the first band
- rate above the first band (p/mile)
Explain this equation
Works out the HMRC simplified mileage allowance for a year's business miles in a car or van.
HMRC pays one rate per mile up to a band limit, then a lower rate above it. min(B, B₁) picks the miles that fall in the first band; max(B − B₁, 0) is any miles above it. Each is multiplied by its rate in pence and divided by 100 to give pounds.
A two-band tariff.
Sense check: 12,000 miles with 10,000 in the first band gives 10,000 at the first rate plus 2,000 at the second.
Watch out: check the current HMRC rates and band each year. Simplified mileage replaces claiming actual vehicle costs; you cannot do both for the same vehicle.
Works out the simplified expenses mileage claim for a car or van used for the business, using HMRC flat rates.
Enter your values to see the result.
Good to know
From 6 April 2026 (tax year 2026 to 2027) the HMRC approved rates for cars and vans are 55p per mile for the first 10,000 business miles and 25p after that; they were 45p and 25p from 2011 to 2026. The increase also applies to self-employed simplified expenses. If you use the flat rate for a vehicle you cannot also claim its fuel, insurance, repairs or capital allowances, and once chosen you must keep using it for that vehicle. Keep a mileage log.
Common mistake
Using the old 45p rate for 2026/27, or counting the daily trip from home to your own workshop. Trips to customers' sites, merchants and the galvaniser are business; ordinary commuting to a permanent workplace is not.
Limits
Cars and vans only (motorcycles 24p, bicycles 20p). Count all business miles in the tax year for the 10,000 band. Check GOV.UK for the current year's rates.
Sources
Results are calculations from the published methods and figures shown, and depend on the data you enter. Follow the welding procedure specification (WPS), BS EN ISO 15614/9606, BS EN 1090, BS EN 1993 and manufacturers’ data. Structural welds need qualified welders and engineered designs.