For several years already, there is an obligation for an employer to disclose information regarding employees, who are assigned to Belgium or who are working under a foreign social security scheme, to the Belgian competent authorities. To this purpose, they have to complete and file a so-called LIMOSA declaration prior to the start of the activities in Belgium.

In case employees are assigned to an affiliated company within an international group or to clients in Belgium, the receiving entity or client has to check whether the LIMOSA declaration was filed. If no such declaration has been made, the obligation to proceed with the filing is with them.

From October 1 onwards, the LIMOSA obligations were extended.

From now onwards, the nature of the work performed is to be indicated on the declaration. In case employees are sent to Belgium by organizations, which are hiring out labour to third parties, the official registration number must be mentioned. Special rules also exist for building activities.

Another novelty is the obligation for the employer to indicate the identity of the liaison person (residing in Belgium or abroad), who has been appointed in Belgium. This person can be an employee or a third party, and can be contacted by inspection authorities in case they need information regarding the employment.

Compliance with the LIMOSA obligations is important as substantial penalties can be imposed on the employer or on the Belgian receiving entity in case of non-compliance.