Guide

The UK Business Mileage Guide

Everything a UK driver needs to know about tracking business miles for tax, in plain English. Works whether you drive for gig platforms, trade jobs, client visits, or an employer who reimburses less than HMRC allows.

01 / Why it matters

Business mileage is money HMRC expects you to claim

Every mile you drive for work in your own car or van is worth something to you at tax time. HMRC allows 45p per mile for the first 10,000 business miles in a tax year, and 25p after that. That number is not a suggestion. It is a tax deduction you are entitled to, and the only reason drivers miss it is poor record keeping.

A driver doing 12,000 business miles a year is looking at £5,000 off their taxable income. At 20% tax, that is £1,000 in their pocket. Drive 18,000 miles and the figure jumps to £6,500 deducted and £1,300 saved. Gig workers routinely cross 20,000 miles a year and never claim a penny of it.

There is also a personal side. Even if you do not drive for work, knowing how much you actually drive is useful. MileClear has a personal mode that tracks milestones, your running costs, and where your car is spending its life. Some of our best testers started tracking to save tax and stayed for the personal insight.

02 / The biggest trap

You cannot claim fuel AND mileage

This is the single most common mistake we see in user imports. The 45p/25p HMRC rate is designed to cover fuel, insurance, servicing, tyres, road tax, and general wear. If you claim the mileage rate, you cannot also claim those costs.

It feels wrong to throw away a petrol receipt. But that is exactly the point of the rate - it does the maths for you. Double-claiming fuel is the fastest way to trigger a HMRC enquiry, and if they find it, they will disallow the whole claim, not just the fuel portion.

The alternative is the "actual costs" method. You keep every fuel receipt, every service invoice, every insurance bill, and claim the business-use percentage of each. For most drivers it is more work and a smaller deduction. The mileage rate wins on simplicity and usually on value.

Pick one method per vehicle and stick with it for as long as you own it. You cannot switch year to year.

03 / What counts

Which trips qualify as business mileage

The short version: any trip where you are driving for work, to a temporary workplace, or between job sites. The long version is mostly about edge cases, and those get their own page.

Counts
  • → Trips between two job sites in one day
  • → Driving to a client or customer
  • → Picking up materials from a supplier
  • → Gig platform deliveries (Uber, Deliveroo, etc.)
  • → Driving to a training course HMRC considers work-related
Does not count
  • → Your daily commute to a permanent workplace
  • → School run, even if you carry on to a job after
  • → Personal errands with a quick work stop
  • → Driving to a social lunch that was pitched as business
  • → Volunteer trips that are not for a registered charity

The grey areas - home-to-first-job, trips that mix business with errands, volunteering - are covered in depth on the what counts as business mileage page.

04 / Record keeping

The log HMRC will actually accept

A reconstructed spreadsheet built from memory at the end of the tax year is not a log. HMRC wants a "contemporaneous record" - something written down at the time, or close to it. Here is the minimum per trip:

  • DateWhen the trip happened
  • Start and endPostcode or full address, not “depot” or “site”
  • ReasonClient, job reference, or platform tag
  • DistanceMeasured, not estimated. Odometer or GPS is fine
  • VehicleRegistration plate of the car or van used

HMRC can open an enquiry up to six years back. A clean log survives an enquiry. A spreadsheet that only appeared after HMRC asked for it does not.

05 / Calculating the deduction

How the 45p/25p split works

The first 10,000 business miles in a tax year are at 45p per mile. Every mile after that, same tax year, is at 25p. The counter resets on 6 April each year.

One of our users - a gig worker splitting their time between Uber and Deliveroo - covered 723.8 miles in two weeks. Annualised, that is around 18,800 miles a year. Their HMRC deduction works out at £4,500 (first 10k at 45p) plus £2,200 (remaining 8,800 at 25p), a total of £6,700. At a 20% tax rate, that is £1,340 saved.

The full worked example, including how the rates apply to sole traders vs employees vs company directors, is on the HMRC mileage rates page.

06 / Tools

What you actually need to track this well

You can do this with a notebook in the glove box. Plenty of drivers have for decades. What breaks down is the discipline - every trip, every day, without fail. Miss a week and you are reconstructing from memory, which HMRC does not love.

The alternative is a phone app that tracks automatically using GPS, tags each trip with a classification and platform, and produces a HMRC-ready export when you need it. MileClear is built for this specifically, for UK drivers - the free tier covers the tracking and the calculation, and the £4.99/month Pro tier adds the PDF and CSV exports you need for Self Assessment or to send to your accountant.

Other apps exist. Pick one that saves you more time than it costs and stops you losing miles.

07 / The personal angle

Why track mileage if you are not claiming tax

Most people vastly underestimate how far they drive. If you had to guess, you would probably come in 30% low. And the things you do with that number - budgeting fuel, planning when to service the car, working out whether an EV makes sense, checking insurance policy limits - only work if the number is real.

The other side is time. A quiet year with a lot of local driving looks very different from a year with two big commutes and a few holiday runs. Seeing the pattern is more useful than most people expect - it shapes how you think about where you live, where you work, and whether you need the second car.

Tracking for personal reasons is free in MileClear and always will be. You never have to turn on the tax side if you do not want to.