New mileage allowance with quarterly indexing starting from 1 October 2026

New amount with quarterly indexation from 1 October 2026

This table shows the new and previous amounts for professional travel (business trips), along with the periods during which they apply:

This amount is based on our own calculations and is therefore still subject to confirmation by the tax authorities. We will, of course, inform you as soon as it is official.

Important

If you do not pay more than the maximum amount according to the indexation system of your sector (see below), you may consider the mileage allowance as a 'cost borne by the employer'. In that case, no social security contributions or taxes are due.

How do you know which system your sector applies?

In certain sectors, a mandatory reimbursement of professional travel with a private vehicle applies. Some sectors adjust the amount quarterly, while others keep an annual adjustment.

It is also possible that your sector does not require mandatory reimbursement, but you as an employer still decide to contribute. In that case, you have the choice, as both the tax authorities and social security accept the mileage allowance with quarterly indexation as well as the mileage allowance with annual indexation.

How to look it up in Lex4You

If your sector requires a contribution, you will find the amount under Joint committees > Your joint committee number > Transport costs > Amounts of transport costs > Professional business travel.

If you find nothing there, then there is no obligation in your sector to contribute to commuter traffic.

Why are there two indexation systems?

The mileage allowance for business trips was traditionally adjusted only once a year on 1 July. However, this proved insufficient to respond quickly to changes in fuel prices. Therefore, policymakers decided to introduce a second system from 1 October 2022, where the mileage allowance is adjusted quarterly. Both systems now exist side by side, so each sector can choose the system that suits them best.

Sources

• Annual indexation: Royal Decree of 18 January 1965 concerning the general regulation on travel expenses and Circular no. 767 - Adjustment of the mileage allowance amount - Period from 1 July 2026 to 30 June 2027, Moniteur belge of 16 June 2026
• Quarterly indexation: Royal Decree of 10 November 2022 amending the Royal Decree of 13 July 2017 establishing the allowances and compensations of the staff of the federal public service