Mileage claim calculator (UK): AMAP, the 10,000-mile step and what's taxable
Most mileage calculators multiply miles by one rate. This one handles the part that actually goes wrong: the claim that crosses 10,000 miles mid-year, passengers, and whether your employer's rate leaves you owing tax or owed relief.
The journey
Rates checked against gov.uk on 15 August 2026: cars and vans 55p to 10,000 miles then 25p, motorcycles 24p, bicycles 20p, passengers 5p each. This covers your own vehicle. Company car fuel uses advisory fuel rates instead.
An employer can pay 55p a mile for the first 10,000 business miles in the tax year and 25p a mile after that, with nothing to report and no tax for the employee (gov.uk). The 55p figure is new: it rose from 45p on 6 April 2026, the first change to the car rate since 2011. Pay more than the approved amount and the excess is taxable pay. Pay less, and the employee can claim the shortfall as tax relief.
The rates, in full
| Vehicle | First 10,000 business miles | Each mile after 10,000 |
|---|---|---|
| Car or van | 55p | 25p |
| Motorcycle | 24p | 24p |
| Bicycle | 20p | 20p |
| Each colleague carried | 5p | 5p |
Only cars and vans have the 10,000-mile step. Motorcycles and bicycles are flat all year, which is why a cycling commuter's claim never needs a running total.
The three things that catch people out
For tax, the approved rate falls to 25p above 10,000 miles. For National Insurance it stays at 55p for every business mile, with no threshold at all. An employer who pays a flat 55p all year is therefore creating a taxable excess on the miles above 10,000 while owing no NI on the same money. Payroll has to treat one payment two different ways, and it is the single most common mileage error we see.
The threshold follows the employee through the tax year (6 April to 5 April) and covers all business miles in their own vehicle, so someone who changes car in October carries their running total across. Someone with two employments starts a fresh 10,000 for each, provided the employers are unconnected.
An employer may pay 5p per mile for each fellow employee carried on the same business journey, tax-free, with nothing to report. But there is no relief attached to it: if the employer does not pay it, the employee cannot claim it from HMRC the way they can claim a shortfall on their own rate. It only exists if the policy creates it.
Paying under the rate: Mileage Allowance Relief
Plenty of employers pay less than the approved amount, and that is allowed. The employee can then claim the difference as Mileage Allowance Relief. It is relief, not a rebate: a £500 shortfall is worth £100 to a basic-rate taxpayer and £200 to a higher-rate one. The calculator above shows the shortfall itself, because that is the figure the claim is made on.
Claims under £2,500 go through a P87 or a personal tax account; above that, through Self Assessment. Either way the employee needs a record of the journeys, which is the practical reason to keep mileage in a system rather than a shoebox.
Company cars are a different scheme entirely
Approved mileage allowance payments are for employees driving their own vehicle. Fuel for a company car is handled by advisory fuel rates, set by engine size and fuel type and revised quarterly on 1 March, June, September and December. From 1 June 2026 they run from 11p to 26p a mile depending on the engine, with fully electric cars at 7p for home charging and 15p for public charging. Applying the 55p rate to a company car is a benefit-in-kind problem, not a mileage claim.
What a good mileage policy settles
- The rate you pay, and whether it matches the approved amount or sits below it.
- Whether the rate drops to 25p after 10,000 miles, or stays flat with the tax consequence handled in payroll.
- Whether you pay the 5p passenger rate at all.
- Whether the journey home counts. Ordinary commuting is not business travel, and the difference between a temporary and a permanent workplace is where most disputes start.
- What evidence a claim needs: postcodes at both ends, purpose, and the running year-to-date total.
Our expenses policy template covers all five in clauses you can paste into a handbook, and the per-diem guide covers the meals side of the same trip.
This calculator applies the statutory rules as published and shows its working, but it cannot know your contracts, your policies or anything unusual about the case. Treat the figure as a starting point, and take advice on anything contested or expensive.
Mileage that keeps its own running total
CoDash tracks business miles per person across the tax year, switches to the lower rate at 10,000 automatically, and shows finance what is approved and what is a taxable excess before it reaches payroll.