How to Claim Tax Back on Mileage Using Form P87: Rates and Limits

To claim tax back on mileage using form P87, you tell HMRC the difference between what your employer paid you per business mile and HMRC’s approved rate, then HMRC refunds tax at your marginal rate on that shortfall. For 2025/26 the approved rate is 45p per mile for the first 10,000 car or van miles, so a basic-rate taxpayer gets 20p back for every £1 of unclaimed mileage and a higher-rate taxpayer gets 40p. The form is only for claims totalling £2,500 or less in a tax year.

Who Can Claim

You qualify if you use your own car, van, motorcycle, or bicycle for business travel and your employer either reimburses you below HMRC’s approved rate or pays nothing at all.¹

Business travel is the phrase that matters. Driving from home to your normal workplace is ordinary commuting and does not qualify. Driving to a client site, a branch office, or any other location where you carry out a specific piece of work does qualify, because HMRC treats it as a temporary workplace.²

There is a limit on how long a workplace stays “temporary.” If you attend a site for what is expected to be more than 24 months, or you spend 40% or more of your working time there over a period exceeding 24 months, HMRC reclassifies it as permanent and the relief stops. The 24-month clock runs from your first visit, not from when you notice the pattern, so start recording early.

One boundary: if your employer pays you more than the approved rate per mile, the excess is taxable earnings reported on form P11D, and P87 is not the right route.³ P87 only helps when you have been underpaid against the approved rate.

The Approved Mileage Rates

HMRC uses flat per-mile rates rather than actual fuel and running costs. For the 2025/26 tax year the Approved Mileage Allowance Payment (AMAP) rates are:⁴

Cars and vans: 45p per mile for the first 10,000 business miles in the tax year, then 25p per mile after that.
Motorcycles: 24p per mile, no tier change.
Bicycles: 20p per mile, no tier change.

If you carry a colleague as a passenger on a business journey, an extra 5p per mile per passenger can be paid tax-free. If your employer does not pay that supplement, you can include it in your claim.³

Check the GOV.UK rates page before you file. The Treasury can change the figures by regulation.⁵

Working Out What You Can Claim

The calculation is simple. Multiply your business miles by the AMAP rate for your vehicle, subtract anything your employer already reimbursed, and the difference is the amount you claim relief on.

A worked example: you drove 4,500 business miles in your car during 2025/26, and your employer paid you 30p per mile.

AMAP entitlement: 4,500 × 45p = £2,025
Employer paid: 4,500 × 30p = £1,350
Shortfall on the P87: £2,025 − £1,350 = £675

The £675 is not the refund. It is the amount HMRC applies your tax rate to. A basic-rate taxpayer would get £135 back (20% of £675); a higher-rate taxpayer would get £270.

If your business mileage passes 10,000 miles, split the calculation. First 10,000 miles at 45p, everything above at 25p. So 14,000 miles with no employer reimbursement in 2025/26 works out as (10,000 × 45p) + (4,000 × 25p) = £5,500.

The £2,500 Limit on Form P87

P87 only handles claims of £2,500 or less per tax year, counting all your employment expenses together, not just mileage.⁶ If your total goes over £2,500, you have to register for Self Assessment and claim through a tax return instead. Add up your figures before you start the form. A driver with 14,000 unreimbursed miles in a car already sits at £5,500, well past the limit.

What the Form Asks For

Gather these before you open the form:⁷

Your name, date of birth, address, and National Insurance number.
Your employer’s name and PAYE reference (on your P60, P45, or payslip, formatted like 123/A246).
The tax year or years you are claiming for.
Total business miles, the AMAP rate you applied, anything your employer paid, and the shortfall.

You can go back up to four years from the end of the tax year in question.⁶ Each tax year needs its own set of figures on the form.

Mileage Log Requirements

For postal claims, you must send copies of your mileage logs with the form. Each journey record needs:⁶

A brief business reason for the trip, such as “client meeting” or “site visit.”
The start postcode.
The end postcode.

HMRC accepts paper logbooks, spreadsheets, and app-generated records. Log trips as they happen. Reconstructed logs, round numbers, and entries like “various client visits” invite questions. Record exact mileage and specific destinations.

Keep your own copy after you submit. HMRC’s guidance for self-employed records is to hold them for at least five years after the 31 January submission deadline for the year concerned, and the same standard is a sensible one to apply here, because HMRC can query your claim well after processing.⁸

Submitting the Claim

You can file online or by post.

Online

The digital route runs through your HMRC personal tax account, which you access with a Government Gateway login. Enter the mileage and employer figures on screen. You get a confirmation reference straight away, and turnaround is usually quicker because the data flows into HMRC’s system without manual keying.

By Post

Download the P87 from GOV.UK, fill it in, sign it, and send it with your mileage logs to:⁷

Pay As You Earn and Self Assessment
HM Revenue and Customs
BX9 1AS

Postal claims without the logs get delayed or rejected. Tracked delivery gives you proof of receipt.

After You File

Postal claims usually take around eight to twelve weeks to process, and online claims tend to be quicker. Turnaround shifts with seasonal demand. Once HMRC checks your figures against your employer’s payroll records, you receive a P800 tax calculation letter explaining the outcome.⁹

Refunds come in one of two forms. For past tax years, HMRC pays you directly by cheque or bank transfer. For the current or upcoming tax year, HMRC often adjusts your tax code so less tax comes out of each payslip, spreading the refund across the rest of the year. The P800 tells you which method applies.¹⁰

If the refund looks lower than your own calculation, check the P800 line by line. Common reasons are HMRC having a different figure for what your employer paid you, or some journeys being treated as disallowed. You can contact HMRC to query the numbers and send more evidence.

Other Expenses You Can Add

Mileage is the most common P87 claim, but the form also covers other unreimbursed employment expenses, provided the combined total stays within £2,500.⁶ Typical additions are uniform laundering costs and working-from-home expenses.

Annual subscriptions to professional bodies can be included too, but only if HMRC has approved the organisation and you paid the fees personally.¹¹ A few conditions apply:

Journal subscriptions only qualify if the letter “J” follows the organisation’s name on the approved list.
Life memberships do not count; only annual subscriptions do.
Fees your employer paid cannot be claimed.

If pulling in these extras takes you above £2,500, the whole claim has to move to Self Assessment.

1
House of Commons Library. Mileage Allowance Payments
2
GOV.UK. Ordinary Commuting and Private Travel (490: Chapter 3)
3
GOV.UK. Expenses and Benefits: Business Travel Mileage – Rules for Tax
4
Legislation.gov.uk. Income Tax (Earnings and Pensions) Act 2003 – Mileage Allowances
5
GOV.UK. Travel – Mileage and Fuel Rates and Allowances
6
GOV.UK. Claim Tax Relief for Your Job Expenses by Post
7
HM Revenue and Customs. Tax Relief for Expenses of Employment (P87)
8
GOV.UK. Business Records if You’re Self-Employed: How Long to Keep Your Records
9
GOV.UK. Tax Overpayments and Underpayments: If You’re Due a Refund
10
GOV.UK. Tax Overpayments and Underpayments
11
GOV.UK. List of Approved Professional Organisations and Learned Societies