Social Security in an International Context

1) Within the European Economic Area and Switzerland

As a general principle, please note that an individual is subject to the social security system of the country in which he is performing his employment.

If an individual carries out employment activities in more than one Member State (i.e. 5% or more of his workdays are spent in another country of the European Economic Area or Switzerland), he is subject to the social security system of the country where he lives if the person works at least 25% in his country of residence. If the person works less than 25% in his country of residence, he is socially insured in the country where the employer is located.

Furthermore, the possibility exists to second an employee to another jurisdiction within the EEA or Switzerland (assuming that he will work less than 5% in another country of the EEA/Switzerland). In such a secondment scenario, the employee can/should (depending on the duration) remain subject to the social security system of the home country.

As from July 1, 2023 the Framework Agreement (FWA) on Cross-Border Telework was put in place. This FWA is a multilateral agreement signed by a number of European countries, including Belgium, to address the social security implications of teleworking across borders—particularly in the context of employees working from home in a different country than where their employer is established.

The FWA aims to provide legal clarity and flexibility for cross-border workers who telework from their country of residence for an employer located in another EU/EEA country or Switzerland. It prevents unintended changes in applicable social security legislation due to occasional or part-time telework across borders.

Under the FWA:

Cross-border teleworking up to 49.99% of total working time from the country of residence (when different from the employer's country) does not trigger a change in social security legislation.
The worker can remain subject to the social security system of the employer's country if:

Both countries agreed on the application of the FWA; and
The activities are habitually carried out in the member states being the employer and the residence state; and
The activities in the residence state are performed through teleworking activities; and
No other activities are performed (e.g. self-employed activities, other employment contract)

2. Outside the European Economic Area and Switzerland

Belgium has concluded bilateral agreements with a significant number of countries. Based on these bilateral agreements, an employee can be seconded to the other jurisdiction and remain subject to the home social security system.

If there is a bilateral agreement concluded between Belgium and the other country , the nature and the extent of the social rights depend on the provisions of the agreement that has been concluded with this country. A certificate of coverage should be requested.

For countries with whom Belgium has not concluded a social security treaty, the local legislation of the two countries will be applicable and for example an affiliation to the Overseas Social Security System (https://www.overseassocialsecurity.be/en/index.html) could be a possibility.