HMRC Business Mileage Claim Calculator
Work out your Approved Mileage Allowance, and whether you're owed tax relief or owe tax on what your employer pays you.
How does the mileage claim calculator work?
HMRC sets "Approved Mileage Allowance Payment" (AMAP) rates — the amount you can be paid per business mile, tax-free, for using your own vehicle for work. If your employer pays you less than the approved rate (including nothing at all), you can claim tax relief on the shortfall — this is called Mileage Allowance Relief (MAR). If your employer pays you more than the approved rate, the excess is a taxable benefit you need to report.
This calculator works out which situation applies to you, the exact amount involved, and — using your tax band — roughly what that's actually worth in cash terms, since mileage relief works by reducing your taxable income rather than paying you the shortfall directly.
3 worked examples
Example 1 — Unreimbursed, basic rate taxpayer
A basic-rate taxpayer uses their own car for 8,000 business miles this tax year and receives no mileage payment from their employer at all.
8,000 miles × 45p = £3,600 (all within the first 10,000-mile tier)
Employer paid:£0
Mileage Allowance Relief claimable:£3,600 shortfall — at 20% tax, this reduces their tax bill by approximately £720
Example 2 — Partially reimbursed, higher rate taxpayer
A higher-rate taxpayer drives 12,000 business miles and is paid 30p/mile by their employer — below the approved rate.
(10,000 × 45p) + (2,000 × 25p) = £4,500 + £500 = £5,000
Employer paid:12,000 × 30p = £3,600
Mileage Allowance Relief claimable:£1,400 shortfall — at 40% tax, this is worth approximately £560 back
Example 3 — Overpaid by employer
An employee drives 5,000 business miles and their employer pays a generous 50p/mile — above the approved rate.
5,000 × 45p = £2,250
Employer paid:5,000 × 50p = £2,500
Result:The £250 excess is a taxable benefit that must be reported — at 20% tax, that's roughly £50 owed, typically collected via a tax code adjustment or self-assessment.
HMRC mileage rates 2026
| Vehicle type | First 10,000 miles | Over 10,000 miles |
|---|---|---|
| Cars and vans | 45p per mile | 25p per mile |
| Motorcycles | 24p per mile | 24p per mile |
| Bicycles | 20p per mile | 20p per mile |
| Passenger payment (cars/vans) | +5p per mile, per passenger — employer's choice, not a right | |
These rates cover fuel, wear and tear, insurance, and depreciation — they are not purely fuel reimbursement. The 10,000-mile threshold resets each tax year (6 April to 5 April) and applies per employment, not per vehicle.
Claiming Mileage Allowance Relief
If your employer pays you less than the approved rate — including paying nothing — you can claim tax relief on the difference. This isn't a direct cash refund of the shortfall; it reduces your taxable income by that amount, so the actual value to you depends on your marginal tax rate.
How to claim depends on the amount. If your claim is under £2,500 for the tax year, you can usually claim via a P87 form online or by post. If it's £2,500 or more, or you already complete one for other reasons, you'll need to claim through Self Assessment instead.
If your employer pays more than the approved rate
The reverse situation is less commonly discussed but equally important: if your employer pays you more than the HMRC approved rate, the excess counts as taxable income. Your employer should report this via payroll (P11D) or payroll benefit-in-kind processes, but it's worth checking your payslips and P11D if you're paid a generous mileage rate, since an unreported excess can create an unexpected tax bill later.
Passenger payments
Separately from the mileage rate itself, employers can choose to pay up to 5p per mile per passenger tax-free, for carrying a fellow employee on a business journey. This is entirely at the employer's discretion — unlike the vehicle mileage rate itself, there's no equivalent relief you can claim from HMRC if your employer doesn't pay it. If you regularly carpool colleagues on business trips, it's worth checking whether your employer's policy includes this.
What this calculator can't tell you
Your exact tax position
The cash value shown assumes your mileage relief or taxable benefit is taxed entirely at the single band you select. In reality, if the amount pushes you across a tax band boundary, part of it may be taxed at a different rate — for large claims near a threshold, the real figure could differ from this estimate.
Whether you're self-employed or employed
This calculator assumes an employed person claiming against an employer's payment. Self-employed people claim mileage differently, as a business expense through their Self Assessment return, using the same AMAP rates but a different mechanism.
National Insurance implications
This calculator focuses on income tax relief. Mileage payments can also interact with National Insurance in some circumstances — check with HMRC or an accountant if your situation is more complex than a straightforward employed mileage claim.
Common mistakes
Forgetting the 10,000-mile tier drops the rate
Many people assume 45p/mile applies to all their business miles. It only applies to the first 10,000 in the tax year — anything beyond that drops to 25p/mile, which significantly changes the approved amount for high-mileage drivers.
Not keeping a mileage log
HMRC can ask for evidence of your business mileage — dates, destinations, purpose, and miles driven. Claims without a contemporaneous log are much harder to defend if queried.
Confusing commuting with business mileage
Ordinary commuting from home to your normal workplace doesn't count as business mileage. Only travel to temporary workplaces, client visits, or other genuine business journeys qualifies.
Missing the claim window
You can typically claim mileage tax relief for the previous 4 tax years, but it's easy to lose track of exactly what you're owed the longer you leave it — claim each year as you go where possible.
How to actually claim
- Keep a mileage log throughout the year — date, destination, purpose, and miles for every business journey
- Check what your employer already pays via your payslips, so you know your actual shortfall or excess
- Claims under £2,500 — use HMRC's online P87 service or form
- Claims of £2,500 or more, or if you already file one — claim through your Self Assessment tax return instead
- Keep records for at least 4 years in case HMRC asks for evidence
How we calculate
Approved amount (cars/vans) = (min(miles, 10,000) × 45p) + (max(0, miles − 10,000) × 25p)
Approved amount (motorcycles) = miles × 24p · Approved amount (bicycles) = miles × 20p
Employer total = miles × employer's rate per mile
If approved amount > employer total: shortfall = approved − employer total (this is your Mileage Allowance Relief claim); estimated cash value = shortfall × your tax rate
If employer total > approved amount: excess = employer total − approved (this is a taxable benefit); estimated tax owed = excess × your tax rate
Passenger allowance = passenger miles × 5p (informational only — tax-free status depends on your employer actually paying it)
Frequently asked questions
What is the HMRC mileage rate for 2026?
45p per mile for the first 10,000 business miles in the tax year, then 25p per mile after that, for cars and vans. Motorcycles are 24p per mile flat, and bicycles are 20p per mile flat.
Can I claim mileage if my employer doesn't pay me anything?
Yes. If your employer pays you nothing for business mileage, you can claim Mileage Allowance Relief on the full approved amount, reducing your taxable income by that figure.
Is mileage relief a direct cash payment from HMRC?
No. It reduces your taxable income, so the actual cash benefit depends on your marginal tax rate — a £1,000 relief claim is worth £200 to a basic-rate taxpayer but £400 to a higher-rate taxpayer.
What happens if my employer pays more than 45p per mile?
The excess above the HMRC approved rate is a taxable benefit. It should be reported via your employer's payroll or P11D process, and you may owe additional tax on it.
How far back can I claim mileage tax relief?
Generally up to 4 tax years from the end of the relevant tax year, though it's best to claim annually rather than let it build up, both for simplicity and to keep your mileage records fresh and easy to evidence.
References & data sources
- HMRC — Travel — mileage and fuel rates and allowances. The official Approved Mileage Allowance Payment rates used directly in this calculator.
- GOV.UK — Mileage Allowance Relief. Official guidance on claiming relief when your employer pays less than the approved rate, including the P87 and Self Assessment routes.
- GOV.UK — Expenses and benefits: business travel mileage for employees' own vehicles. Guidance for employers on approved and excess mileage payments.
This calculator provides a simplified estimate and is not a substitute for advice from HMRC or a qualified accountant, particularly for claims near a tax band threshold or with a more complex tax position.