Chain liability for illegal employment

If your indirect (sub)contractor in the contracting chain employs irregularly staying third-country nationals as an employee or self-employed person, then, as the principal, main contractor or intermediate contractor, you can only be held liable if you had prior knowledge of this. The inspection services must demonstrate this.

If your direct (sub)contractor employs irregularly staying third-party nationals as an employee or self-employed person, then as principal, main contractor or intermediate contractor, you can be held liable. There are two possible situations.

1. Your direct (sub)contractor belongs to one of the risk sectors

These risk sectors are:

• The construction sector (works in real estate, supply of ready-mixed concrete);
• The cleaning sector;
• The meat sector (slaughtering, cutting, meat preparation);
• Parcel handlers commissioned by postal services (open definition) .

As a professional principal, main contractor or intermediate contractor using a direct (sub)contractor from one of these risk sectors, you must satisfy two requirements to avoid your liability as of 1 January 2026:

• Be in possession of a written declaration in which your direct (sub)contractor confirms that it does not or will not employ irregularly staying third-country nationals as an employee or self-employed person;
• Complying with the duty of diligence.

2. Your direct (sub)contractor does not belong to one of the risk sectors

As a professional principal, main contractor or intermediate contractor using a direct (sub)contractor from a sector other than these risk sectors, you must satisfy one requirement to avoid your liability as of 1 January 2026:

• Be in possession of a written declaration in which your direct (sub)contractor confirms that it does not or will not employ irregularly staying third-country nationals as an employee or self-employed person.

The duty of diligence does not apply in this case.

1. The passport or travel document of the foreign worker or self-employed person;
2. Residence permit for more than 3 months in the Member State where the foreign worker or self-employed person resides;
3. Proof of enrolment in the Limosa database. This document is unnecessary if an exemption from the Limosa reporting duty applies;
4. The A1 certificate confirming that the foreign worker or self-employed person is affiliated with the social security system in the Member State from which that person is posted. The acknowledgement of receipt of the document request is also sufficient.

1. The passport or travel document of the foreign worker or self-employed person;
2. Proof of valid residence in Belgium or a single permit;
3. Proof of a valid Belian Work Permit or a single permit for employees/proof of a valid professional card in the case of self-employed persons;
4. Proof of enrolment in the Limosa database. This document is unnecessary if an exemption from the Limosa reporting duty applies.

1. The passport or travel document of the foreign worker or self-employed person;
2. Proof of valid residence in Belgium or a single permit;
3. Proof of a valid Belgian Work Permit or a single permit for employees/proof of a valid professional card in the case of self-employed persons;
4. Proof of enrolment in the Limosa database.

To make a report through the Reporting Office, you must identify yourself so that your report is made in the name of your organisation (and not as a natural person). Data from the National Social Security Office (NSSO) are used for this purpose.

As a foreign company without a Belgian CBE number, you cannot register with the NSSO. Therefore, you cannot use the Reporting Office.

Would you like to report a breach? Then request a PDF form from the Vlaamse Sociale Inspectie at ketenaansprakelijkheid.wewis@vlaanderen.be(opens in your email application). You then complete the PDF form and return it to the Vlaamse Sociale Inspectie via email. Only then have you complied with the duty of diligence and you can no longer be held liable.

The direct (sub)contractor may transfer a copy of documents containing personal data of foreign workers or self-employed persons to:

• the principal (if the contractor works directly for the principal);
• the contractor one level up the chain (if it is a subcontractor).

• The regulations explicitly provide a legal basis for this action so that it complies with privacy laws (GDPR) (in Dutch).
• Submission of the documents is necessary to fulfil the duty of care and to enable the principal or contractor one level up the contracting chain to review the documents and keep them available for the social inspection services.

• Within the framework of the transparency obligation included in Articles 13 and 14 GDPR, it is recommended to make contractual agreements with the contractor or subcontractor regarding the obligation to inform the data subject about the processing of their personal data in the context of chain liability.
• The processing manager is reminded of the principle of purpose limitation. The data may only be processed in the context of chain liability and thus not used for other purposes.
• Records may be kept for a period of five years after the completion of the project in question.
• The collection and retention of this data must be done with respect for data protection principles by taking the necessary technical and organisational measures:
  • Only the documents listed may be requested/shared to minimise the data processing operation.
  • The documents must be stored securely and should only be accessible to authorised persons.
  • Processing managers are reminded of the responsibility to appoint a processor who provides adequate safeguards with respect to the application of appropriate technical and organisational measures