Mileage Tax Relief Calculator, 2026/27
If your employer reimburses business mileage below the HMRC approved rate, or not at all, you can claim mileage allowance relief on the shortfall. This calculator estimates the tax refund due at your own marginal rate.
The mileage tax relief calculator runs on the rates and thresholds HMRC has published for the 2026/27 tax year, so the figures you see reflect the position your company is actually filing on rather than a historic set of bands. Change any input and the result recalculates immediately, with no sign-up and nothing sent anywhere.
If you are a director of a UK limited company, use it as a first look before a decision rather than as the decision itself. Mileage allowance relief is the gap between the AMAP entitlement and whatever the employer actually reimburses, taxed at your marginal rate rather than paid pound for pound. Real company positions bring in other income, reliefs, group structures and prior year adjustments that a single page of inputs cannot see, which is why the workings are written out below under personal & self assessment tax. Read those, then check the numbers against your own accounts, and speak to us if anything looks materially different from what you expected.
Last reviewed 12 September 2026 for the 2026/27 tax year. Reviewed by Waqas Sagar, Member of ICAEW, Fellow of ACCA, Fellow of AAT.
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Result, 2026/27
Tax relief you can claim
Unused mileage allowance
Entitlement less what your employer already paidFull AMAP entitlement
Already reimbursed by employer
Illustration only, figures are based on the rates you have selected and the information entered. Please check your own position with us before acting.
Estimates for the 2026/27 tax year using published GOV.UK rates. Switch between 2026/27 and 2025/26 above.
How this is calculated
This tool first works out the full AMAP entitlement for your business mileage: £0.55 per mile for the first 10,000 miles and £0.25 per mile after that. It then compares this to what your employer actually pays per mile, and the difference is the unused allowance.
Unlike the employer's tax-free payment, mileage allowance relief is not paid out in full. HMRC gives relief at your marginal rate of income tax on the shortfall, so a higher rate taxpayer recovers 40% of the gap and a basic rate taxpayer recovers 20%.
This is a different calculation from the mileage allowance calculator elsewhere on this site, which simply shows what an employer can pay tax-free. This one is aimed at the employee working out what they can personally reclaim from HMRC.
How to claim
Claims of £2,500 or less are usually made using form P87, either online or by post, and can typically be backdated up to four tax years. Larger claims, or claimants who already complete a self-assessment return, should include the figure on the employment pages instead.
You will need your employer's PAYE reference, a record of business miles travelled and the rate your employer actually reimbursed, which is normally shown on payslips or an expenses report.
Common situations
Many employers pay a flat rate, such as 20p or 25p per mile, well below the 45p AMAP rate, particularly for mileage between multiple client sites. Some pay nothing at all and expect the employee to claim relief directly.
Where an employer pays above the AMAP rate, there is no relief to claim; instead the excess is added to taxable pay and should already appear on the P11D or payslip.
What this means for your company
Treat the result as a planning figure for the 2026/27 tax year. If it changes what you were about to do, take a director's salary, a dividend, a large asset purchase or a filing decision, check it against your own accounts first. We can review the position with you and confirm the tax treatment before you commit.
Frequently asked questions
How far back can I claim mileage tax relief?
HMRC generally allows claims for the past four tax years, so a claim made in the 2026/27 tax year can usually reach back to 2022/23, provided you can still evidence the mileage and the rate paid.
What if my employer pays nothing towards mileage?
You can still claim relief on the full AMAP entitlement at your marginal rate, since the whole amount is then an unused allowance rather than a partial shortfall.
Do I need a mileage log to claim?
Yes. HMRC can ask for evidence of business journeys, so keep a record of dates, destinations, purpose and miles travelled, ideally alongside your employer's mileage reimbursement statements.
Is mileage relief the same as claiming fuel costs?
No. The AMAP rate already bundles fuel, insurance, servicing, depreciation and other running costs into a single mileage rate, so you cannot separately claim actual fuel receipts on top.
Keep going
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