Travel expense reports and mileage allowance: what the documentation must include
As of 1 January 2026, the state mileage allowance rate is NOK 5.30 per kilometre, of which NOK 3.50 is tax-free. But whichever rate you use, it’s the documentation that determines whether the allowance holds up in an audit. Here are the requirements for a valid mileage log and travel expense report.
What the mileage log must include
For the mileage allowance to hold up in a bookkeeping audit, each individual trip must be documented with the date, start and end location (address or place name), the exact number of kilometres driven, and the purpose of the trip – for example which customer, project or meeting it concerned. Inadequate documentation can, in the worst case, result in the entire allowance being treated as taxable.
Checklist for each trip
- Date of the trip
- Start and end location with address or place name
- Exact number of kilometres
- Purpose: customer, project or meeting
- Signature or approval from the traveller
The 2026 rates
The state mileage allowance rate for 2026 is NOK 5.30 per kilometre. Of this, NOK 3.50 per kilometre is tax-free, as set by the Directorate of Taxation. The difference of NOK 1.80 per kilometre is treated as taxable salary, and the employer must calculate withholding tax and employer’s national insurance contributions on this amount. Toll, ferry and parking expenses come in addition and are documented separately with a receipt.
Consequences of missing documentation
The Norwegian Tax Administration can set aside all or part of the allowance if the mileage log is incomplete. Our recommendation is fixed routines with monthly submission of travel expense reports, ideally combined with a digital mileage log with position logging, so that the documentation is in place on an ongoing basis instead of having to be reconstructed afterwards.
Employee or sole proprietorship – remember the difference
For employees, the mileage allowance is paid by the employer based on the travel expense report, with tax withheld on the portion exceeding the tax-free rate. If you run a sole proprietorship and use your own car in the business, different rules apply for how the car costs are deducted in the business accounts. If you’re unsure which set of rules applies to you, you should clarify this with your accountant before applying the rates.
We set up digital travel expense reports and mileage logs integrated with your accounts, whether you use Tripletex, Conta, PowerOffice Go, Fiken or eAccounting.
Ongoing review that travel expense reports meet the documentation requirements, as part of your regular bookkeeping.
Would you like good routines in place for travel expense reports and mileage allowance? Book a no-obligation chat with us.
