Joint liability for contractors in Belgium: risks and how to avoid them
Working with a contractor who owes the NSSO or the tax authorities? You can become liable for those debts yourself. Here is how it works and how to rule out the risk.
What does joint liability mean?
Joint liability allows the NSSO or the FPS Finance to collect your contractor's debts directly from you, as if they were your own. It applies to construction work and the other sectors covered by article 30bis.
There are two separate regimes:
| Social security debts (NSSO) | Tax debts (FPS Finance) | |
|---|---|---|
| Legal basis | Art. 30bis Act of 27 June 1969 | Art. 402 Income Tax Code 92 |
| When | Contractor has social debts when the contract is concluded | Contractor has tax debts when the contract is concluded |
| Cap for the client | 50% of the total price excluding VAT | 35% of the total price excluding VAT |
When are you liable?
The risk exists when your contractor owes the NSSO or the tax authorities at the moment you conclude the contract. Whether you knew about it does not matter. Checking before you sign the order or contract is therefore essential.
Private individuals having work done for strictly private purposes are not covered.
How it differs from the withholding obligation
Joint liability and the withholding obligation are two sides of the same system:
- Withholding applies to every payment. If the contractor has debts at that moment, you withhold 35% for the NSSO and 15% for the FPS Finance and transfer those amounts.
- Joint liability applies when the contract is concluded. Amounts you correctly withhold and transfer are deducted from your liability.
A client who fails to withhold when required may also have to pay the amounts that were not withheld, on top of the debt they are already liable for.
An example
You sign a contract of € 100,000 excluding VAT with a contractor who owes € 80,000 in social security debts at that time. Your social liability can reach € 50,000. If you correctly withhold 35% on every payment, those transfers are deducted from that amount.
How to rule out the risk
- Check before the contract. Check the contractor for social and tax debts before signing. Keep the dated result.
- Check again before every payment. What counts is the situation on the day the payment is actually executed. See also how to check social security debts and tax debts.
- Withhold and transfer when the check shows debts, and pay only the balance to the contractor.
- Keep your proof. In an audit you must be able to show when you checked and with what result.
Automatic instead of manual
With many suppliers, manual checking is error prone. With the withholding check, Checkplicht checks your suppliers with the NSSO and the FPS Finance at once, stores every result as proof and alerts you when a status changes. Try it free for 7 days.
Frequently asked questions
Am I liable if I did not know my contractor had debts?
Yes. Liability depends on the contractor's situation when the contract is concluded, not on your knowledge of it.
What is the maximum joint liability?
For the client, at most 50% of the total price excluding VAT for social debts and 35% for tax debts.
Does this apply to private individuals?
No. Natural persons having work done for strictly private purposes are excluded.
Is one check at the start of the works enough?
No. The check at contract stage protects against liability, but the withholding obligation must be checked again at every payment.
This text is general information, not legal advice. When in doubt, consult the NSSO, the FPS Finance or your adviser.
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