Concurrence of contractual and tort liability

Currently the application of Belgian tort law between contracting parties is limited. Decades ago, the Belgian Supreme Court ruled that by entering into a contract, parties tacitly waive their right to claim damages under tort law if such damages were caused by a breach of contract. Consequently, such damages can only be claimed based on the contractual liability of the defaulting party. In other words, concurrence between contractual and extra-contractual liability is the exception rather than the rule in Belgian law.

The Belgian Supreme Court previously identified three exceptions to this rule. These exceptions are situations in which the damages are the result of a breach of contract that (i) is punishable under criminal law, (ii) forms a mixed fault (tort and contractual) resulting in only extra-contractual damages or (iii) is governed by regulatory law.

The legislator has now reversed the legal principle. After the entry into force of the new Book 6, concurrence will become the rule. In case of a contractual default, the injured party will henceforth have the choice to pursue legal action based on either contractual or tort law to see its damages compensated.

As doctrine and case law had already aligned the scope of damages of contractual and tortious liability, this change is not expected to have far-reaching consequences.

The relevant provisions being of a supplementary nature, the parties can also choose to set aside this new regime.

Abolition of the quasi-immunity of auxiliaries

However, concurrence becoming the rule does haven an important impact on the legal position of auxiliaries. An auxiliary is a person or entity entrusted by the debtor of a contractual obligation with the full or partial performance of that obligation. Under current law, such an auxiliary enjoys quasi-immunity from the claims of the principal. Under current law the principal can only bring a claim against its own contractual counterparty and not against the auxiliary, except under the specific exceptions for concurrence mentioned above. This is called the quasi-immunity of the auxiliary person.

This reform seeks to provide the ability to claim damages directly from the party who effectively caused the damage. Moreover, the possibility for the principal to claim from the auxiliary may be convenient in the event of the debtor's insolvency.

The new Book 6 will abolish this quasi-immunity. The principal will thus be able to claim extra-contractual damages from the auxiliary with whom he has no contractual relationship. However, parties can rule out this possibility in the contract between the principal and the debtor and/or in the contract between the debtor and auxiliary.

In absence of a specific clause excluding the application of the tort liability of the auxiliary, he/she may nevertheless protect himself against tort claims by invoking contractual defenses (e.g., limitation of liability, exoneration clauses, statute of limitations).

These contractual defenses can be based both on the contract the auxiliary has concluded with the debtor as well as on the contract between the principal and debtor. This second source can only be useful to the extent that the auxiliary has knowledge of the contents of the contract between the principal and the debtor.

This reform thus allows principals to seek redress directly from auxiliaries of their debtor. This implies the exposure of, amongst others, company directors, freelancers, independent subcontractors, and employees to a new type of claim made by a party they indirectly provide services for, potentially without prior knowledge of this party’s identity.


The changes to Belgian tort law mark a significant shift from previous practice. The concurrence of contractual and tort liability broadens the scope for claims, while the abolition of the quasi-immunity of the auxiliary may lead to an increase in claims against auxiliaries. Particular attention will need to be paid not only to contractual clauses between the debtor and the principal, but also between the debtor and the auxiliary.

As these changes enter into force, it will be interesting to observe their impact on the Belgian legal landscape. These changes could potentially lead to a fairer distribution of liability and a more comprehensive protection of the rights of victims, or to an increase in the exposure of the unwitting auxiliary.