Making a declaration of start of employment to the social security

Last update

The employer must affiliate newly appointed employees with the social security administration.

This is done by sending a declaration of start of employment for a private-sector employee (déclaration d'entrée pour salarié du secteur privé) to the Joint Social Security Centre (Centre commun de la sécurité sociale - CCSS) for each employee, either on paper or electronically via SECUline.

The declaration will enable the CCSS to:

  • register the new employee;
  • establish, collect and recover the employee's contributions;
  • distribute the contributions between the different competent institutions.

Temporary work agencies are required to register their temporary workers via SECUline ('DECINT' procedure).

Who is concerned?

The declaration of start of employment for a private-sector employee must be filled in by the employer for:

Partners or directors/business managers

The declaration of start of employment for a private-sector employee must also be filled in, in the case of a company, for:

  • any partner holding more than 25 % of the company shares and who is listed as business manager on the business permit;
  • the members of the board of directors who are listed as business manager on the business permit.

Although these persons will have self-employed status, businesses must use the standard registration form for employees (or the 'DECAFF' procedure via SECUline) and not the registration form for self-employed workers.


Preliminary steps

On registering an employee for social security, it is assumed that:


The employer must register with the CCSS within 8 days following the entry into service of the 1st employee; his registration remains valid throughout the existence of the business.

How to proceed


An employer who hires a person in return for remuneration must, in order to affiliate him to the CCSS, submit a declaration of start of employment for a private-sector employee within 8 days following the entry into service of the new employee.

In the event of late submission of the declaration of start of employment (more than 30 days late), the Joint Social Security Centre will fine the employer EUR 50 for each month of delay (with a maximum limit being EUR 2,500).

Registration can also be done online via SECUline ('DECAFF' procedure).

If, at the time of affiliation, the employee has not yet received a national identification number (matricule - 13-digit social security number) from the CCSS, the employer must:

  • state on the declaration the date of birth of the employee (in the format: year, month, day);
  • attach a copy of their identity document (identity card or passport).

Error or change in the situation

If there is a material error when registering an insured person (e.g. erroneous date of employment), the employer can issue a corrective declaration by ticking the box "Déclaration rectificative" on the same form.

However, if there is a change in the registration of the insured person regarding the different risks at the level of social security (e.g.: changing from a manual to an intellectual activity), the employer must send a new declaration of start of employment.

Upon receipt of the declaration of start of employment for the new employee, the CCSS will provide, in order to verify the information:

  • to the newly insured employee: an acknowledgement of receipt of the declaration stating the essential data listed in the declaration;
  • to the employer: a list of salaries, established on a monthly basis and which enables the employer to double check if all their declarations have been received by the CCSS and if eventual changes have been duly implemented.

Data required

In order to complete the declaration of start of employment, the employer must have the following data.

Information concerning the insured person:

  • the insured person's national identification number;

  • surname and first name;

  • full address.

Information on the professional activity of the insured person:

  • exact description of the activity;

  • number of work hours per week;

  • if the salaried worker is carrying out a manual activity or not;
    This information is used to determine the category of workers for which an additional premium must be paid to the CCSS for the benefit of the Employers' mutual insurance scheme (Mutualité des employeurs);

  • the 4-digit employment code corresponding to the exact activity of the insured party according to the new nomenclature ISCO-08 (International standard classification of occupations);

  • country in which the insured person carries out his professional activity.

Data in relation to the status of the insured person:

  • is the business permit registered in the name of the insured person;

  • if the salaried worker is the manager, director or assistant director responsible for daily business management;

  • the percentage of shares held by the insured person in the business.

Online services and forms

Who to contact

Joint Social Security Centre

  • Joint Social Security Centre

    4, rue Mercier L-2144 Luxembourg Luxembourg
    L-2975 Luxembourg
    (+352) 40141-1
    08.00 - 16.00
    Email address:
    Closed ⋅ Opens Monday at 8.00
    8.00 to 16.00
    8.00 to 16.00
    8.00 to 16.00
    8.00 to 16.00
    8.00 to 16.00

    The reception desks can only be visited by appointment.

Related procedures and links



Further information

Legal references

Your opinion matters to us

Tell us what you think of this page. You can leave us your feedback on how to improve this page. You will not receive a reply to your feedback. Please use the contact form for any specific questions you might have.

Fields marked with an asterisk (*) are mandatory.

Did you find what you were looking for?*
How would you rate this page?*
Very poor
Very good

Leave a comment to help us improve this page. Do not provide any personal information such as your email address, name, telephone number, etc.


Please rate this page

Your opinion has been submitted successfully!

Thank you for your contribution. If you need help or have any questions, please use the contact form.

Would you like to help us make digital public services more user-friendly by submitting your suggestions for improvement?

Then visit Zesumme Vereinfachen, the online participation platform dedicated to administrative simplification in Luxembourg.

Let's simplify things together

An error occurred

Oops, an error has been detected during your form processing.