Interpretation of the 5%-rule for applying EU-Regulation 883/2004


In order to determine whether someone should be considered as working in one Member State only with limited travel to other Member States or as being simultaneously employed in different Member States, one should – amongst others – determine whether or not the activities carried out outside the country of usual employment take up 5% of the overall working time and/or total salary of the employee.

The National Social Security Office (RSZ/ONSS) has now sent out a newsletter about the (new) interpretation of this so-called 5%-rule.

Only activities that take up more than 5% in one single Member State will be considered as non-marginal activities and will thus lead to the application of the reference rules for simultaneous employment.

Until now, the authorities however took the view that as soon as an employee spends more than 5% of his time outside his country of usual employment (even if this was not more than 5% in one single Member State), he should be considered as being simultaneously employed.

Some caution is nonetheless required as the RSZ/ONSS will still carry out a case-by-case evaluation, also taking into account some other criteria such as the nature of the activities (e.g. ancillary activities or not).