This solidarity system is guaranteed as working people must pay a contribution in proportion related to their income. Unions, insurances and employer's organisation manage the system together.
The Belgian social security has 3 functions :
The standard social security system is made by 7 branches:
If you have a professional activity in a company, this one has the obligation to be affiliated to the social insurance organisation of its choice.
The ID number is called NISS (numéro d'identification de la sécurité sociale). A card, named SIS, is given that holds the NISS number. The insured person will use the card in all the procedures with social security institutions, and with people in charge of making declarations to those organisations (employers, pension funds for example, and of course the insured person).
The ONSS (Office national de sécurité sociale) collects and pays the social contributions from the employers. Those contributions include the personal contributions of the employees and the share of the employers. In summary, the Belgian social contributions are shared such as the employee pays about 13% of his/her gross salary and the employer pays 25% (i.e. a total of 38%).
The Belgian Social Security website is http://www.socialsecurity.be and the website of the Federal Public Service is: http://www.securitesociale.fgov.be