Since April 2, 2024, new declaration rules for your employees’ professional activities abroad are in effect. These new procedures replace the cross-border telework form that had been applicable since July 1, 2023, in accordance with the framework agreement.

From now on, any activity performed from abroad by your employees (whether telework, business trips, training, secondments, or multi-activity) must be subject to a mandatory declaration to the Joint Social Security Center (CCSS), either electronically via SECUline or on paper (DEMSDET procedure). Here is what you need to know to fully understand these new obligations.

Basic principles to know

Affiliation to a single social security scheme

Two principles should be remembered:

• An employee can only be subject to one national social legislation for the same working period.
• As a general rule, the employee is affiliated with the social security of the country in which they work.

Possible exceptions

However, if your employee works temporarily or partially abroad, exceptions provided by European regulations allow maintaining their affiliation to Luxembourg’s social security. For this, the employer must undertake certain steps to obtain the A1 certificate, which confirms the applicable social security scheme for the worker. This certificate is required for any activity in the European Union (EU), the European Economic Area (EEA), Switzerland, and the United Kingdom. For other countries, a specific attestation must be issued.

Three situations requiring an A1 certificate

Secondment abroad

Secondment concerns employees temporarily sent by their employer to another Member State to carry out a professional activity, whether it’s a meeting, a client visit, training, or occasional work abroad.

Regular activities in multiple member states

Employees regularly performing professional activities in multiple Member States of the EU, EEA, Switzerland, or the United Kingdom must obtain an A1 certificate. This document is essential to determine the applicable social security scheme.

Telework of non-resident employees

Cross-border telework constitutes a case of simultaneous employment in multiple Member States. Here again, an A1 certificate is necessary to maintain affiliation in Luxembourg.

How to declare a professional activity abroad?

Declaration before the start of the activity

Regardless of the situation (telework, secondment, multi-activity), the declaration must be made before the start of the activity abroad. The corresponding form is available on the CCSS website, under the “employers” section, then “private sector” and “activities abroad.”

In case of secondment

When the employer sends an employee on secondment to another Member State or third country, they must submit a declaration via SECUline or fill out a specific paper form (“Secondment Request”). The CCSS will assess the compliance of the request with Luxembourg and European legislation to decide whether affiliation to Luxembourg’s social security can be maintained during the secondment period.

In case of regular activities in multiple states

For employees regularly performing activities in multiple countries, the employer must also submit a declaration to the CCSS. The form to fill out is the same, whether for residents or non-residents.

• For Luxembourg residents: The CCSS determines if affiliation in Luxembourg is applicable and issues the A1 certificate if the conditions are met.
• For non-residents: The social security organization of the country of residence is competent to determine the applicable legislation.

In case of telework

For cross-border telework, the same form used for multi-activity must be completed. It is the social security organization of the employee’s country of residence that will determine the applicable legislation.

Information required for the declaration

To complete the form, you will need to provide the following information:

• Details about the employer and the employee,
• Start and end dates of the secondment, telework, or multi-activity period,
• Percentage of activity in each concerned country (distinguishing telework from other activities),
• Indication of any other professional activity performed by the employee (if applicable).

This information is crucial to ensure that the employee is covered by the correct social security scheme during their periods of work abroad.

By following these procedures, you ensure your company’s compliance with the new social security regulations and facilitate the administrative management of employees carrying out assignments abroad.