Are you planning to second your employees to Belgium ? Before you begin your project, it's worth understanding your key responsibilities. This article explains the secondment process step by step, what the ConstruBadge card is, and what the pay rates are in the construction sector. You'll also find a practical table of employee costs in 2025.
Under what conditions can workers be posted to Belgium?
The posting of workers from Poland to Belgium is carried out in accordance with European Union regulations – in particular Directive 96/71/EC and its amendment 2018/957. Additionally, Belgian national regulations, including collective bargaining agreements (CCTs) applicable in a given sector, must be observed.
Conditions of legal delegation:
the employee has an A1 form (insurance in Poland),
was reported to the LIMOSA system,
receives a salary not lower than the Belgian sectoral minimum wage .
Mandatory LIMOSA registration – what do you need to know?
Before an employee begins work in Belgium, they must register on the LIMOSA portal. Once registered, the company receives an L1 document, which the employee must carry with them throughout the posting period.
❗ Failure to report may result in a fine of up to €18,000 per employee.
ConstruBadge – a mandatory identification badge on Belgian construction sites
In the construction sector (CP 124) , the ConstruBadge card is required – a personal ID required on every construction site.
What does ConstruBadge contain?
Employee's name and surname
Photo
Number ONSS
Name of the delegating company
How to get it?
The company must register employees in the CheckIn@Work system, which allows for daily registration on the construction site. The card itself is issued by the Constructiv organization.
Minimum wage rates in Belgium - gross cost table
Posted workers must be paid in accordance with Belgian law. Below is a table of construction worker costs for 2025.
Construction worker employment costs (CP 124) – 2025
| Qualification level | Minimum gross rate/hour | Gross monthly salary (168 h) |
|---|---|---|
| Helper | 17,15 € | 2 882,20 € |
| Skilled worker | 18,70 € | 3 141,60 € |
| Certified specialist | 20,10 € | 3 376,80 € |
In Belgium, the standard full-time work week is 38 hours . This translates to approximately 168 hours per month (38 hours × 4.4 weeks). This conversion helps:
comparison of hourly and monthly wages,
simulation of employment costs,
preparation of offers and calculations for clients.
🔎 Note: In some sectors different standards apply (e.g. 36 h or 40 h per week), so always check the relevant collective bargaining agreement (CCT) .
Do I have to pay Belgian contributions or will Polish ZUS be sufficient?
Scenario 1: Delegation with A1 (ZUS)
If the company obtains an A1 form , the employee is still subject to Polish ZUS contributions and not Belgian ONSS contributions.
Conditions:
The company actually operates in Poland,
The employee is employed in Poland and was previously insured,
Work in Belgium is temporary (up to 24 months),
The employee does not replace another person.
➡ In such a case:
contributions go to ZUS,
but Belgian working and pay conditions must be ensured (rates, working hours, health and safety, etc.).
Scenario 2: No A1 - registration obligation in Belgium
If ZUS does not issue an A1 or the posting does not meet the conditions:
the company must register with the Belgian ONSS,
pays Belgian contributions (approx. 35% + gross salary),
is treated as a local employer .
⚠️ Note: The Belgian inspection may question the posting and A1 if it considers it to be fictitious (e.g. the work is permanent or the company does not actually operate in Poland).
Additional responsibilities when posted to Belgium
In addition to LIMOSA and ConstruBadge, the posting company must:
Translate documents into French, Dutch or German ,
Provide on-site contract, A1 , time records, payroll,
Appoint a contact person in Belgium (so-called liaison person ),
Register your company for VAT if it provides taxable services.
- Pay income tax in Belgium after 183 days.
Penalties for non-compliance – what to avoid?
| Infringement | Potential punishment |
|---|---|
| No LIMOSA notification | €1,800 – €18,000 per employee |
| Break A1 | Recalculation of contributions, financial sanctions |
| Wage dumping | Penalty for underpaid wages |
| Brak ConstruBadge | Construction work ban, fines |
🔥 A company may also be placed on the Belgian liste noire (blacklist), which makes it difficult to continue operating on the market.
Summary and Support
Posting employees to Belgium is a huge opportunity for company growth, but it requires full compliance with regulations. From documentation, through registration and contributions, to sector-specific payroll details, everything must be perfect.
Do you need support?
– Template of a delegation agreement
– Document Checklist
– Assistance with LIMOSA, A1 and ConstruBadge
Contact us – we will be happy to help you delegate legally and safely.
