Employer registration with the CCSS
Published on 10 October 2026 · Updated on 10 October 2026
In short
To register as an employer in Luxembourg, every new employer, whether an individual or a company, files an operating declaration with the Joint Social Security Centre (CCSS) no later than 8 days after the first employee starts. The CCSS then issues an employer number. Each employee is declared separately through an entry declaration.
Key points
- Deadline
- 8 days after the 1st employee starts
- Document
- Operating declaration
- Number issued
- Employer number
- Late entry declaration
- €50 per month, capped at €2,500
Becoming an employer
- 1
Hold the permit
Where the activity requires it, the business permit must be obtained from the Ministry of the Economy before registering.
Ministry of the Economy - 2
Complete the operating declaration
13-digit national identification number, company details and a description of the activity. A Luxembourg company attaches only the documents not filed with the RCS; a foreign employer attaches a recent extract from its trade register.
Employer or agent - 3
File with the CCSS
By form or through MyGuichet.lu.
Employer or agent - 4
Receive the employer number
The CCSS issues the employer number and the contribution class linked to the activity.
CCSS - 5
Declare each employee
Entry declaration within 8 days of hiring, on paper or online through SECUline.
Employer or payroll provider
Two declarations not to confuse
The operating declaration registers the business as an employer, once. The entry declaration enrols each employee, at every hire. A 30-day tolerance applies to the entry declaration; beyond it, the CCSS may impose a fine of €50 per month of delay, capped at €2,500.
Good to know
The employer number remains valid for the whole life of the business, unless the legal form changes. A change from SARL-S to SARL or from SARL to SA must therefore be reported to the CCSS.
The manager is not always an employee. A manager who holds more than 25% of the shares of a SARL or SARL-S is enrolled as a self-employed worker: see CCSS enrolment for the self-employed. Payroll, monthly declarations and the calculation of contributions then fall to a payroll provider or your licensed accountant: we do not handle them.
Next step
Hiring your first employee?
We prepare and file the operating declaration with the CCSS.
Frequently asked questions
When do you have to register as an employer with the CCSS?
Guichet.lu sets the deadline at 8 days after the first employee starts. In practice, it is better to file the operating declaration before hiring, so the employer number is available when the employee is declared. The business permit must be obtained beforehand if the activity requires one.
What is the difference between the operating declaration and the entry declaration?
The operating declaration registers the business as an employer and leads to the employer number. The entry declaration enrols each employee hired, within 8 days of the start date. Both are compulsory and separate: one does not replace the other, and missing one often blocks the next.
What does an employer risk by declaring an employee late?
A 30-day tolerance is accepted. Beyond it, the CCSS may impose a fine of €50 per month of delay, capped at €2,500, according to Guichet.lu. A missing declaration can also complicate the employee’s coverage, notably in the event of illness or an accident.
Can a foreign company register as an employer in Luxembourg?
Yes. A foreign employer with staff in Luxembourg files an operating declaration and attaches a recent copy of its entry in the trade register of its country. European coordination rules then determine which social security legislation applies to each employee.