New information regarding the changes to the special tax regime for inbound taxpayers and inbound researchers – Belgian social security point of view
In our newsletter of 22 December 2025 we provided an overview of the changes to the special tax regime for inbound taxpayers and inbound researchers implemented retroactively since 1 January 2025 on a tax level.
The Belgian social security authorities just published interim instructions in which it is confirmed that these tax changes will for the time being not be fully implemented on a social security level.
It follows that there will be a difference in the tax treatment vs. the social security treatment of an inbound taxpayer or researcher provided that such a person is covered by Belgian social security.
This difference can be highlighted as follows:
| Tax | Social security | |
| Annual gross remuneration > € 70.000 | yes | yes |
| Cost allowance | 35% | 30% |
| Cap allowance € 90.000/year | no | yes |
It goes without saying that this difference triggers an additional layer of complexity for the payroll of an inbound taxpayer or researcher subject to Belgian social security.
It's time to act!
E-mail tax@propay.be if:
- You would like more information about the special tax regime;
- You would like assistance with the preparation and submission of the (special) application for special tax regime;
- You would like assistance in relation to re-evaluating existing compensation packages and/or employment contracts.
