Flemish Duty of Care in Construction (belgium, 2026): What Clients, Contractors & Subcontractors Must Do Now

Since 1 January 2026, the Flemish duty of care Belgium framework has imposed a binding obligation on every professional client, main contractor and subcontractor active in the construction sector within the Flemish Region to verify, document and monitor the lawful employment status of workers engaged through subcontracting chains. The obligation goes well beyond the written declaration that previously shielded parties from chain-liability exposure: it now demands proactive due diligence, on-site checks and a verifiable audit trail. Failure to comply exposes each link in the contracting chain to administrative fines, civil chain liability and, in the most serious cases, criminal prosecution for facilitating illegal employment of third-country nationals.

This guide sets out the statutory basis, the obligations for each party, a practical compliance checklist, contract-drafting guidance and a phased implementation timeline that in-house counsel, contracts managers and site teams can put to work immediately.

Executive Summary: What Changed and the Five Immediate Actions

The Flemish Government’s amended chain-liability and duty of care framework entered into force on 1 January 2026 after having been postponed from its originally planned start date. The rules apply to all construction and cleaning-sector activities performed in the Flemish Region that exceed established threshold amounts. Every entity in the contracting chain, from the professional client who commissions the work, through the main contractor, down to each tier of subcontractor, now bears a distinct set of verification, documentation and reporting duties. The enforcement mechanism is chain liability: if a subcontractor further down the chain is found to employ illegally residing third-country nationals, each upstream party that failed to discharge its duty of care can be held jointly and severally liable.

Industry observers expect the practical effect to be a significant increase in pre-contract and on-site compliance activity. The five actions every organisation working on Flemish construction sites should take without delay are:

• Contract audit. Review every live subcontract and framework agreement for compliant warranty, audit-right and flow-down clauses.
• Document requests. Issue standardised onboarding questionnaires to all direct subcontractors requiring KBO extracts, social-security registration, payroll evidence and work-permit documentation.
• Site reporting procedures. Establish a site document register and a clear internal reporting route for irregularities.
• Insurance check. Confirm with brokers that employer’s liability, third-party liability and professional indemnity policies do not exclude chain-liability claims arising from the duty of care in Flanders.
• Compliance lead. Appoint a named individual responsible for duty-of-care compliance on each project or site.

What the Flemish Duty of Care Requires: Statutory Basis and Scope

Statutory Source and Effective Date

The duty of care obligation is embedded in the Flemish chain-liability framework targeting illegal employment. The relevant decrees and implementing decisions (Besluiten van de Vlaamse Regering, or BVR) were published in the Belgian Official Gazette (Moniteur belge / Belgisch Staatsblad) and are consolidated in the Codex Vlaanderen. According to the official guidance published by the Flemish Government on vlaanderen.be, the duty of care obligation applies from 1 January 2026 to clients and (sub)contractors active in the construction sector within the Flemish Region. This replaced the earlier regime under which a simple written declaration from a subcontractor was, on its own, sufficient to escape liability.

Scope: Which Activities, Thresholds and Exemptions

The duty of care in construction covers works that fall within the broadly defined construction and cleaning sectors in Flanders. However, as noted in the Flemish Government’s official chain-liability guidance, the duty of care does not apply in the construction and cleaning sectors when the work falls below the established threshold amounts. It also does not apply to parcel-delivery services. Activities above the threshold, including residential, commercial, infrastructure and renovation projects, are fully within scope. Private individuals commissioning small residential works in a non-professional capacity are generally not classified as “clients” under the decree, but any entity procuring construction services in a professional or commercial capacity is covered.

Understanding whether a specific project falls within or outside the thresholds is a critical first step in any compliance assessment under the Flemish duty of care Belgium framework.

Who Must Comply: Obligations by Role for the Flemish Duty of Care

Obligations of the Client (Professional Client)

The professional client, meaning any entity that commissions construction work in a commercial or professional capacity, must ensure that its procurement processes and contractual arrangements satisfy the duty of care. This means verifying that the main contractor it engages is compliant, incorporating express contractual warranties relating to lawful employment, and maintaining a monitoring system for the duration of the project. The client is not merely a passive participant: it must take active steps to satisfy itself that its direct contractor is discharging its own downstream obligations.

Obligations of Main Contractors

Main contractors carry the heaviest operational burden. They must verify the legal status of every direct subcontractor before work begins, obtain the prescribed documents (discussed below), supervise on-site compliance, and report any irregularities to the relevant authorities without delay. The main contractor must also ensure that social and working conditions on site meet Flemish and federal requirements.

Obligations of Subcontractors

Every subcontractor must provide proof of legal employment and social-security registration for all workers it deploys, comply with the site policies established by the client and main contractor, and cooperate fully with any compliance audits. Subcontractors that engage their own sub-tier contractors must in turn discharge the same duty of care obligations downstream.

Practical Compliance Checklist: What to Change on Site and in Contracts Right Now

This section is the operational core of the duty of care construction compliance programme. It translates the statutory obligations into concrete steps that site managers, procurement teams and legal departments can implement immediately.

Site Operational Steps

On every Flemish construction site, the following operational procedures should be in place from day one:

• Worker onboarding. Every worker arriving on site for the first time must present valid identification. Site management should record each worker’s identity, employer and social-security status in a centralised digital or paper register before granting site access.
• Badge and access control. Implement a badge or check-in system that links each worker to a verified subcontractor. This provides real-time visibility of who is on site and supports the audit trail required by the duty of care.
• Toolbox talks. Include a brief compliance module in regular toolbox talks, reminding workers and foremen of the duty to report irregularities and of the documentation that must be available for inspection.
• Reporting route. Establish a clearly communicated internal reporting route, a named compliance lead or hotline, through which any person on site can flag suspected irregularities regarding illegal employment or missing documentation.
• Spot checks. Conduct unannounced spot checks at least monthly, verifying that workers on site match the subcontractor’s declared workforce and that valid work permits, social-security registrations and employment contracts are on file.

Contractual Steps

Construction contracts update 2026 requirements demand the following minimum clause set in every subcontract, framework agreement and purchase order:

• Compliance warranty. The subcontractor warrants that all workers it deploys (whether employees or self-employed) hold valid work and residence permits and are registered with the appropriate social-security authorities.
• Audit and inspection rights. The client or main contractor reserves the right to audit the subcontractor’s employment records, visit sites and request supporting documentation at any time during the contract and for a defined period after completion.
• Flow-down obligation. The subcontractor must impose equivalent duty-of-care obligations on any sub-tier contractors it engages and must provide evidence of having done so upon request.
• Indemnity. If a breach of the compliance warranty causes the upstream party to incur chain-liability exposure, the subcontractor indemnifies the upstream party for all resulting costs, fines and damages.
• Suspension and termination rights. The upstream party may suspend work or terminate the subcontract with immediate effect if the subcontractor fails to cure a documented compliance breach within a specified cure period.

Sample Clauses

The following sample clauses are provided as starting points. They should be reviewed, localised and adapted to each project’s specific circumstances before inclusion in any agreement.

Sample compliance warranty:

“The Subcontractor warrants and undertakes that all personnel deployed under this Agreement, whether employed or self-employed, are lawfully entitled to reside and work in Belgium, are duly registered with the applicable social-security institutions, and that the Subcontractor has obtained and will maintain all permits, registrations and declarations required under the Flemish duty of care legislation and any applicable federal employment law.”

Sample audit clause:

“The Client and/or Main Contractor shall have the right, upon reasonable notice (which in urgent cases may be given orally and confirmed in writing within 24 hours), to inspect, audit and take copies of the Subcontractor’s employment records, payroll documentation, social-security registrations and work-permit files. The Subcontractor shall cooperate fully and make all relevant records available without undue delay.”

Immediate Actions Checklist for Subcontractor Due Diligence Belgium

1. Distribute standardised onboarding questionnaire to every direct subcontractor.
2. Collect and verify: KBO/BCE extract, VAT registration, social-security affiliation certificate, sample payslips and work permits for non-EEA workers.
3. Check the subcontractor’s status on the Crossroads Bank for Enterprises (KBO) and confirm no outstanding social-security debts via the NSSO/RSZ online portal.
4. File all documents in a project-specific compliance register, tagged by subcontractor and date received.
5. Set a recurring diary entry to re-verify documentation at defined intervals (recommended: every 90 days or upon any change in the subcontractor’s workforce).

Chain Liability and Enforcement: When a Written Declaration Is NOT Enough

How Chain Liability Works in Flanders

Chain liability for illegal employment in Flanders means that if a subcontractor at any tier in the contracting chain is found to employ illegally residing third-country nationals, every upstream party, from the main contractor to the professional client, can be held jointly and severally liable for the resulting sanctions and costs, unless that party can demonstrate that it fulfilled its duty of care. The chain-liability mechanism is the primary enforcement tool for the construction liability Flanders framework and is explicitly described in the Flemish Government’s official guidance on vlaanderen.be.

Evidence Standard: What Officials Will Look For

According to the Flemish Government’s official guidance, in addition to providing a written statement, parties must also comply with the duty of care to avoid liability. This means obtaining a number of documents from direct subcontractors and maintaining an active monitoring regime. A written declaration from a subcontractor confirming that it does not employ illegally residing workers is necessary but is no longer sufficient on its own to escape criminal sanctions or chain-liability exposure.

Enforcement officials will look for evidence that the upstream party took concrete, verifiable steps, not just passive, paper-based assurances. Industry observers expect inspectors to focus on the following red flags:

• Inconsistent payslips. Payroll records that do not match the number or identity of workers observed on site.
• Sudden subcontractor turnover. Frequent and unexplained changes of subcontractors, particularly where new subcontractors are not subject to proper onboarding.
• Cash payments. Any indication that workers are being paid in cash rather than through documented payroll channels.
• Missing or expired work permits. Workers on site who cannot produce valid identification or whose work permits have lapsed.
• Absence of an audit trail. No records of document requests, verifications or site checks by the upstream party.

Criminal and Administrative Exposure

Parties that fail to comply with the Flemish duty of care face a range of potential consequences. Administrative fines may be imposed directly by the competent Flemish authorities. In the most serious cases, particularly where an upstream party is found to have knowingly or recklessly contracted with a subcontractor employing illegally residing third-country nationals, criminal prosecution is possible under both Flemish regional decrees and federal law. The Federal Public Service Employment, Labour and Social Dialogue (FOD WASO) coordinates cross-jurisdictional enforcement actions, meaning that Flemish inspectors and federal labour inspectors may share intelligence and conduct joint inspections.

Contracts and Clause Drafting: Practical Drafting Notes for Construction Contracts Update 2026

Clause Bank: Essential Provisions

Every construction contract executed for works in the Flemish Region should now include, at minimum, the following provisions to satisfy the duty of care in Flanders:

• Compliance warranty. An express representation that all workers are lawfully employed and properly registered (see sample clause above).
• Audit and inspection rights. A contractual right for the upstream party to audit employment records and inspect the site at any time (see sample clause above).
• Flow-down obligation. A requirement that the subcontractor imposes equivalent obligations on its own subcontractors and provides evidence of having done so.
• Indemnity for chain-liability loss. A clause requiring the defaulting subcontractor to indemnify the upstream party for any fines, costs or damages arising from a breach.
• Withholding and suspension mechanism. The right to withhold payment or suspend works if a compliance breach is identified and not cured within a defined period.
• Termination for material breach. An express termination right triggered by a failure to cure a documented duty-of-care breach.

Practical Drafting Tips

When drafting or redlining construction contracts for Flemish duty of care Belgium compliance, practitioners should bear several practical points in mind. First, ensure that the compliance warranty is drafted as a continuing obligation rather than a one-off representation at the point of signing, subcontractor workforces change throughout a project. Second, the audit clause should specify that reasonable notice may be as short as 24 hours in urgent circumstances, and should clarify who bears the cost of audits (the early indications suggest that upstream parties typically absorb audit costs unless a breach is found). Third, flow-down clauses should require the subcontractor not only to include equivalent language in its own subcontracts but also to provide copies of those clauses on request.

Finally, withholding provisions should include a mechanism for releasing withheld sums once the breach has been satisfactorily cured, to avoid disputes over payment timing.

Insurance, Bonds and Risk Transfer

The introduction of the duty of care in construction raises important questions about insurance coverage. Many standard employer’s liability and third-party liability policies were written before the 2026 changes and may not expressly contemplate chain-liability claims arising from a failure to discharge the Flemish duty of care. Professional indemnity policies, meanwhile, may contain exclusions for regulatory fines or penalties.

The likely practical effect is that contractors and clients will need to engage their insurance brokers to review existing policy wordings. Specific actions to take include:

• Request a coverage opinion. Ask each insurer to confirm in writing whether chain-liability claims under the Flemish decree are covered, excluded or subject to sub-limits.
• Check professional indemnity exclusions. Verify whether fines, penalties and administrative sanctions are excluded, and if so, whether endorsements or extensions are available.
• Review bonds and guarantees. Confirm that any performance bonds or parent-company guarantees provided by subcontractors remain valid and sufficient in light of the additional chain-liability exposure.
• Consider chain-liability endorsements. Explore whether specialist endorsements or standalone policies are available to cover the specific risks introduced by the duty of care.

Implementation Timeline and Next Steps

Given that the duty of care obligation is already in force, the focus should be on catching up and embedding compliance procedures as rapidly as possible. The following phased timeline provides a practical action plan:

Early indications suggest that enforcement activity will ramp up throughout 2026, with coordinated inspections between Flemish regional inspectors and federal labour authorities. Organisations that have not yet implemented the measures outlined above should treat this as an urgent priority.

Sources

1. Vlaanderen.be, Chain Liability for Illegal Employment
2. Codex Vlaanderen, Flemish Decrees and Implementing Decisions
3. Belgian Official Gazette (Moniteur belge / Belgisch Staatsblad)
4. Federal Public Service Employment, Labour and Social Dialogue (FOD WASO)
5. Vlaams Parlement, Committee Minutes and Debates