Keeping a mileage record: what must be in it?
Written by Ilias Aarrass7 min read · Published on · Last reviewed on 
In short
A watertight trip record holds the date, odometer readings, departure and arrival address, business purpose and nature of each trip, plus the car's make, model and registration.
- With a private car you deduct 0.25 euros per business kilometre; fuel, insurance, tolls and parking are already included.
- With a company car you avoid the addition by staying under 500 private kilometres a year.
- One missing private trip can bring down the whole record and costs the addition for the entire year.
- You keep the trip record for seven years, like the rest of your records.
Whether you want to deduct the mileage allowance or avoid the addition, a good mileage record is indispensable. The tax authorities set hard requirements for what it must contain, and this is the item that most often goes wrong in audits. This article explains exactly which data are mandatory, how to keep the record watertight and what a gap costs you.
When do you need a mileage record?
You need a mileage record in two situations, and the requirements differ considerably. With a private car it is about what you may deduct; with a company car about the addition to your income.
| Using a private car for business | Company car | |
|---|---|---|
| What it achieves | Deduct € 0.25 per business kilometre | Avoid the addition |
| What you record | Only your business trips | All trips, business and private |
| The limit | No limit | At most 500 private kilometres a year |
| What a gap costs | Those kilometres lapse as a deduction | Full addition over the whole year |
What must be in the record?
For every trip you record the same details. It sounds like a lot of work, but with an app it takes seconds per trip. Record the make, model and registration of the car once as well, plus the period in which you used it. These are the mandatory fields per trip.
- The date of the trip.
- The start and end reading of the odometer.
- The departure and destination address, not just the town name.
- The route taken if it differed from the usual one, for example due to a diversion.
- The business purpose: which client, which assignment, which appointment.
- Whether the trip was business or private. With a company car, private trips too.
Commuting counts as business
Unlike for employees, commuting is business travel for an entrepreneur with a company car. Driving from home to a client and back are simply business kilometres. A detour to the supermarket on the way is not: that part is private and must be recorded separately.
How do you keep it watertight?
A trip record must be watertight: the tax authorities must find no gaps or unexplained kilometres. So keep it consistently and immediately, not afterwards from memory. There are apps and devices that register trips automatically, which prevents errors and saves time.
Why is this so important?
Without a watertight record you cannot deduct the mileage allowance or avoid the addition. With a company car an incomplete record can mean you still owe the full addition, with an assessment covering several years. In a books investigation this is one of the first things the inspector asks for.
Worked example: 9,000 business kilometres in your private car
- Business kilometres in the year
- 9,000 km
- Allowance per kilometre
- € 0.25
- Deduction from your profit
- € 2,250
Result: At a rate of around 37 per cent that saves over € 830 in tax. Without a record that deduction is zero
Frequently asked questions
What mileage allowance applies in 2026?
Twenty-five cents per business kilometre with a private car. That amount covers everything: fuel, maintenance, insurance and depreciation. You cannot deduct those costs separately alongside it; see travel costs and the mileage allowance.
Does commuting count as business?
For an entrepreneur, yes. Trips between your home and a client or your work address are business kilometres. For employees it is different; a separate scheme applies there.
May I reconstruct my kilometres afterwards?
Better not. A reconstruction from your diary can serve as supporting evidence, but a record built up afterwards often does not survive an audit. So log trips immediately.
What happens if one trip is missing?
With a private car you only lose the deduction for that trip. With a company car it is more serious: the record is then not watertight and the tax authorities can impose the addition over the whole year.
Is an app mandatory?
No, a notebook or spreadsheet is fine too, as long as all mandatory data are included. An app or tracking device records automatically and prevents gaps, which with a company car can make the difference.
How long must I keep my trip record?
Seven years, like the rest of your records. See record retention. Keep it digitally, because paper trip books get lost.
Sources
- Requirements for a trip recordBelastingdienst · belastingdienst.nl
- Business use of a private vehicle in 2026Belastingdienst · belastingdienst.nl
Sources checked on
This article provides general information based on the rules known for 2026 and does not replace personal tax advice. For your specific situation, we're happy to take a look with you.
