Business Mileage Logs for Year-End
If you drive for work, every business mile can matter at tax time, but only if you can prove it. A tidy mileage log turns scattered trips into a clear record your accountant can trust. This guide shows you what a business mileage log should include, how to fill gaps before the year ends and how to set up a simple habit so next year's log almost writes itself.
Key takeaways
- A good mileage log records the date, start and end points, purpose and miles for each business trip, plus odometer readings at the start and end of the year.
- In the US, the IRS standard mileage rate was 72.5 cents per mile for 2026 business use. Check IRS.gov for the rate that applies to your tax year.
- In the UK, company cars are a taxable benefit in kind, and mileage rules depend on whose vehicle it is. Check current HMRC guidance.
- If your log has gaps, rebuild them now from calendars, invoices and receipts while the details are still fresh.
Early November is the ideal time to check your log. You have most of the year's trips behind you, the busy holiday season is about to start, and your memory of October and September is still reasonably clear. Waiting until January means piecing together a whole year from scraps, usually in a hurry.
A quick note: this article is general information about mileage records, not tax or legal advice. Rules on what counts as business travel, which costs you can claim and how vehicles are taxed vary by country and change over time. Check official guidance from the IRS or HMRC and ask an accountant or tax adviser about your own situation.
Why a mileage log matters
Tax authorities generally expect you to support vehicle claims with records. A log written as you go is far more convincing than a rough estimate made at year-end, and it protects the deduction or allowance you are entitled to if questions come up later.
A clear log also helps in ways that have nothing to do with tax:
- You can see how much time and money driving really costs your business.
- You can bill clients accurately if your contracts allow you to charge for travel.
- You can spot routes or regular trips that could be combined or replaced with a call.
- You can reimburse employees fairly when they use their own vehicles.
What usually counts as business mileage
Trips to meet clients, visit job sites, collect supplies, attend training or travel between work locations are commonly treated as business travel. Ordinary commuting between home and a regular workplace is generally not. The exact lines depend on your country's rules and on details such as whether your home is your main place of business, so check the official guidance or ask your accountant if you are unsure.
Common mistake
Logging round numbers for every trip, such as "about 20 miles" each time you visit a client. Repeated round figures look like estimates. Use your odometer or a map route for each trip, even if it takes a few extra seconds.
What every business mileage log should include
Whether you keep a paper notebook, a spreadsheet or an app, each entry should capture the same core details.
- Date of the trip.
- Starting point and destination. A business name or address works well.
- Business purpose. Short and specific: "Site visit, kitchen refit for client" beats "work."
- Miles driven, taken from odometer readings or a reliable route measurement.
- Vehicle used, if you have more than one.
- Who drove, if employees also use the vehicle.
In addition, record your odometer reading on the first and last day of the year. This lets you work out total miles driven, so you can show the split between business and personal use.
A simple mileage log template
Copy these columns into a spreadsheet. The rows below are made-up examples for illustration only.
| Date | From | To | Business purpose | Start odometer | End odometer | Business miles |
|---|---|---|---|---|---|---|
| 2027-10-04 | Home office | Client, Oak Street | Quote for office redesign | 48,212 | 48,229 | 17 |
| 2027-10-04 | Client, Oak Street | Supplier warehouse | Collect sample materials | 48,229 | 48,241 | 12 |
| 2027-10-06 | Home office | Training center | Safety course for new equipment | 48,305 | 48,338 | 33 |
Add a totals row at the bottom of each month and a summary tab that adds the months together. That makes the year-end total a single number you can hand to your accountant.
Pro tip
Take a dated photo of your odometer on the first working day of each month. It costs ten seconds and gives you a reliable checkpoint if you ever need to rebuild a missing stretch of the log.
US: the standard mileage rate vs actual expenses
In the US, many small business owners and self-employed people choose between two methods for claiming vehicle costs: the standard mileage rate or actual expenses.
The standard mileage rate
You multiply your business miles by the IRS rate for that tax year. It is simple and needs fewer receipts for running costs, though you still need a good mileage log. Some costs, such as business parking and tolls, are commonly claimed separately. Rules on when you can use this method, and when you can switch, are specific, so check current IRS guidance.
Actual expenses
You add up the real costs of running the vehicle, such as fuel, insurance, repairs, registration and depreciation, then claim the business-use share based on your mileage records. This takes more record keeping but can suit some vehicles and situations better.
Either way, your mileage log is the backbone of the claim, because it shows the business-use percentage. Your accountant can help you decide which method fits.
UK: company cars, own vehicles and mileage allowances
In the UK, how mileage is treated depends heavily on whose vehicle it is.
- Company cars. A car provided by the business that is available for private use is generally a taxable benefit in kind for the employee, and there are reporting duties for the employer. Business mileage records still matter, for example when fuel is involved.
- Employees using their own vehicles. Employers can usually reimburse business mileage at HMRC's approved mileage rates without tax, provided the records support it. Check the current rates on GOV.UK.
- Sole traders and partners. Self-employed people can often choose between simplified expenses using flat mileage rates or claiming actual vehicle costs. The rules about which option you can use, and when you can change, are specific.
Because UK Self Assessment returns and balancing payments are due by 31 January, getting your log in order before Christmas leaves time for your accountant to prepare the return calmly.
How to rebuild a log with gaps
Most people discover gaps when they first look properly at their log. Do not panic, and do not invent trips. Instead, rebuild honestly from the records you already have.
- List your sources. Calendar entries, invoices, client emails, delivery notes, fuel receipts, parking receipts and phone location history (if you have it turned on) can all show where you went and when.
- Work month by month. Go through your calendar and mark every appointment that involved driving.
- Measure each trip. Use a map to measure the route between the addresses rather than guessing.
- Note the purpose. Match each trip to an invoice, quote or project so the purpose is clear.
- Mark rebuilt entries. Add a note such as "rebuilt from calendar and invoice" so you and your accountant know which entries were reconstructed.
- Check against odometer readings. If you have service records or photos with odometer readings, make sure your totals are realistic.
Hypothetical example
Imagine Tom, a self-employed electrician who kept a good log until a busy summer, then stopped. In early November he spends an evening with his calendar and job invoices. He finds 46 jobs between July and October, measures each route on a map and adds a supplier run he can see on his card statement every Friday. Each rebuilt entry is labeled, and his service invoice from August confirms the odometer reading roughly matches. It takes him about three hours, much less than he feared, and his records are now complete enough to give his accountant.
Common mistake
Mixing personal detours into business trips. If you stop at the gym on the way back from a client, only the business part of the route counts. Log the direct business distance and leave out the personal leg.
Building a habit for next year
The easiest year-end is one where the log is already done. Choose one method and stick with it.
- Paper notebook in the glove box. Low tech and reliable, as long as you write in it after every trip.
- Spreadsheet on your phone. Use the template above in a shared spreadsheet so entries sync across devices.
- A mileage tracking app. Many apps record trips automatically using your phone's location. Check current features, pricing and privacy policies, and review the trips weekly so personal journeys are not tagged as business.
Whatever you choose, set a weekly reminder, perhaps every Friday afternoon, to check the week's entries and add any missing purposes. Five minutes a week is much easier than five hours in January.
Your year-end mileage log checklist
- Find your odometer reading from the start of the year
- Review the log month by month and highlight gaps
- Rebuild missing trips from calendars, invoices and receipts
- Label rebuilt entries clearly
- Add monthly totals and a yearly business-miles total
- Record your odometer reading on the last day of the year
- Collect parking and toll receipts for business trips
- Check the current IRS rate or HMRC guidance for your tax year
- Send the summary to your accountant well before the filing deadline
Frequently asked questions
How long should I keep my mileage logs?
Keep them for as long as your tax authority could ask about the related return, which is often several years. The exact period depends on your country and situation, so check IRS or HMRC guidance and ask your accountant.
Can I estimate my mileage instead of keeping a log?
Estimates are much harder to defend if questioned. If you have gaps, rebuild them from real records such as calendars and invoices rather than guessing, and keep a contemporaneous log going forward.
Do I need separate logs for each vehicle?
Yes, it is clearer to keep a separate log, or at least a separate column, for each vehicle. That way each vehicle's business-use share is easy to calculate.
Does my mileage app count as a valid log?
An app can be a convenient way to record trips, but the record still needs the core details: date, route, purpose and miles. Review and correct trips regularly, and export a copy at year-end for your files.
Related reading
The bottom line
A business mileage log only needs a few details per trip, but it needs them consistently. Check your log now, rebuild any gaps from real records, total your business miles and note your year-end odometer reading. Then check the current IRS rate or HMRC rules before you or your accountant prepare the return.
Spend one evening this month getting the log in shape, then set a weekly five-minute reminder for next year. Your future self, filing taxes in January, will thank you.
