Employees and company owners who travel professionally in their own cars are entitled to a flat-rate mileage allowance for this purpose.
However, it isn't easy to determine the exact cost of these trips.

This is why the tax authorities work with a flat-rate allowance per kilometre driven, which is independent of the actual cost of the trip: the so-called flat-rate kilometre allowance.

Both the tax authorities and the NSSO accept this flat-rate allowance, as long as the maximum amount per kilometre driven is not exceeded. For a long time, this ceiling amount was indexed annually, on the 1st of July.

Annual and quarterly indexing

Since the 1st of October 2022, the regulation on the kilometre allowance for business trips has been adjusted to better respond to fluctuations in fuel prices. Instead of only annual indexation based on the RD of 13 July 2017, the kilometre allowance is now also indexed quarterly.

Which system to choose?

Both systems currently coexist. Depending on the joint committee under which your company is located, it may have been determined whether the quarterly adjustments, or the annual adjustment, should be followed.

If there is no specific provision, one is free to choose which system to apply. Do note: "Employers who opt to apply the flat-rate system on an annual basis must adhere to it for the entire period from 01.07.2023 to 30.06.2024. They cannot switch to the quarterly flat-rate system during that period." (Circular 2023/C/78, 18/09/2023).

Current ceiling amounts and history

Quarterly indexation

The current ceiling amounts with quarterly indexation and their history can be found below:

PeriodAllowance per driven kilometre
01/10/2023 - 31/12/2023€ 0,4259 / km
01/07/2023 – 30/09/2023€ 0,4237 / km
01/04/2023 – 30/06/2023€ 0,4246 / km
01/01/2023 – 31/03/2023€ 0,4259 / km
01/10/2022 – 31/12/2022€ 0,4201 / km

Yearly indexation

The current ceiling amounts with yearly indexation and their history can be found below:

PeriodAllowance per driven kilometre
01/07/2023 – 30/06/2024€ 0,4280 / km
01/07/2022 – 30/06/2023€ 0,4170 / km
01/07/2021 – 30/06/2022€ 0,3707 / km