The information required
The official sources list several items, which can be grouped. The information requested covers the firm, the workers and the site.
On the posting employer: identity, address, electronic and telephone contact details.
On the contact person: identity, address and contact details of the individual or entity present on the territory for the duration of the work, who will communicate with the administration.
On location: the address or addresses of the workplaces in Luxembourg, and the address where documents will be kept.
On the mission: the nature of the activity carried out on national territory and the expected duration of the posting, start and end dates.
On the employee: surname, first name, place of habitual residence, date of birth and nationality.
On the contractual chain: the identity, address and contact details of the direct subcontractor, and the accommodation of the employee posted.
That last category deserves attention: it means the subcontracting structure is disclosed to the administration.
| Element | What it contains | When |
|---|---|---|
| Posting declaration | Firm, workers, site, duration | Before starting |
| Social badge | Individual identification of the worker | During the work |
| Update | Any change of situation | Without delay |
The timing of the declaration
A point without ambiguity.
The declaration must be made at the latest as work begins on Luxembourg territory.
An earlier declaration remains possible, and is preferable in practice.
There is therefore no period for regularisation after starting: beginning work without having declared puts the firm in default immediately.
This distinguishes posting from most other administrative obligations, which often tolerate a period.
What the social badge is
A simple document whose absence is nonetheless visible. The social badge is carried and shown at inspections.
Once the declaration is made, the employer prints a social badge for each employee posted.
It carries a code allowing the administration to access the data supplied in the declaration.
It must be produced on inspection, and it aims to simplify verification that the posting rules are observed.
Its function is therefore to make compliance immediately verifiable on site, which makes it the first item requested at an inspection.
An employee present without a badge is an immediate signal, covered in the article on site inspections.
The duty to report changes
A continuing duty, often forgotten.
Any change must be reported to the administration through the same channel, notably a change of contact person, of the place where documents are kept, or of accommodation.
The declaration is therefore not a single act, but the opening of a monitoring that lasts as long as the work.
On a long project several of these elements change, and each calls for an update.
What to prepare before declaring
Four items, to gather beforehand.
Full identification of each employee posted.
Effective appointment of the contact person, who must be present on the territory.
The address in Luxembourg where documents will be kept.
The details of the direct subcontractor, where the work forms part of a chain.
The second condition is the most demanding in practice, since it presupposes a real presence rather than a formal appointment.
What this means for a professional
Four rules.
Declare before starting, later regularisation not existing.
Gather the employee details beforehand, the declaration being by name.
Treat the badge as a site document, immediately available.
Update the declaration on every change, notably of contact person.
This article reflects the rules at the date of checking and serves professional orientation. It does not constitute legal advice.