The first variable: origin
It determines whether freedom to provide services applies. The first variable is the origin of the firm.
A firm established in the European Economic Area or in Switzerland enjoys freedom to provide services, which considerably lightens the formalities for access to the activity.
A firm established outside that area must hold a business permit for any occasional and temporary activity on Luxembourg territory.
This difference is the most structural of the three. It cannot be circumvented and it conditions the whole administrative path.
It concerns the firm's place of establishment, not the nationality of its directors or its employees.
| Variable | What it determines | Where to check it |
|---|---|---|
| Origin of the firm | Whether freedom to provide services applies | Constitution and registered office |
| Profession practised | The notification requirement | List of regulated professions |
| Duration of the work | Whether the temporary regime continues | Contract and programme |
The second variable: profession
It determines the obligation to notify.
Craft and industrial firms are subject to an obligation to notify the provision of services.
Firms in commercial or liberal professions subject to a business permit are exempt from any obligation to notify. This category includes architects and engineers in particular.
This exemption is surprising, since it benefits precisely the most regulated professions.
It is explained by the fact that these professions are supervised through other channels, notably professional bodies, as the article on who must notify develops.
The third variable: duration
It determines whether the temporary regime continues to apply. The third variable is the duration of the work.
Occasional and temporary work falls under a lighter regime, suited to a defined mission.
A prolonged or repeated presence may tip the situation into establishment, with the consequences covered in the article on when work becomes establishment.
This variable is the least predictable of the three, since it is assessed case by case rather than against a single threshold.
It is also the one that changes during a project, a site extending without anyone re-examining the applicable regime.
How they cross
The crossing produces very different situations. Two neighbouring firms may fall under distinct regimes.
European firm, liberal profession, short mission: the lightest regime, with exemption from notification, but posting and insurance obligations maintained.
European firm, craft trade, short mission: notification required, plus posting and insurance obligations.
Firm outside the European area, whatever the profession: business permit mandatory, even for occasional work.
Any situation, whatever the combination, prolonged over time: examination of the tipping point into establishment.
No combination dispenses with the posting obligations, which follow their own logic.
The method for placing your situation
Four questions, in this order.
Where is the firm established, in the sense of where its activity is actually carried on.
Under what professional regime does it practise in Luxembourg, craft, industrial, commercial or liberal.
What is the expected duration of the work, and is it liable to extend.
Will employees be sent on site, which triggers the posting obligations whatever the answers to the first three.
The fourth question is independent of the others, and it is the one most often forgotten.
What this means for a professional
Four rules.
Ask the three questions before committing, not at the point of starting.
Do not infer the regime from European origin alone, profession and duration also playing a part.
Handle the posting obligations separately, they do not follow the same rules.
Re-examine the regime when a project extends, duration being the most mobile variable.
This article reflects the rules at the date of checking and serves professional orientation. It does not constitute legal advice.