Adoption of Book 9, Title 1 of the New Belgian Civil Code: Reform of Personal Securities
14 Oct 2025
On 1 January 2026, the law of 5 June 2025 adopting Title 1 of Book 9 of the new Civil Code will enter into force. This law modernises the Belgian regime of personal securities and offers a global and coherent legal framework.
Book 9, Title 1 of the new Civil Code, which shall repeal articles 2011 to 2043octies of the former Civil Code, has a broader scope than its predecessor: on one hand, the traditional concept of cautionnement / borgtocht has been replaced by the broader term “personal securities” and, on the other hand, other personal securities are codified (e.g. the autonomous personal security, the letter of comfort and joint and several liability). These instruments now enjoy a clear legal basis, thereby reducing judicial uncertainty. Under the former regime, only cautionnement / borgtocht had a statutory foundation.
The text is mostly of a suppletive nature, meaning that the parties can derogate from it, except for the definitions and if the law provides otherwise – in the case of a regime of personal security granted by a consumer, for example. That being said, the general principles developed under the old Civil Code regime remain largely applicable.
The main innovations and codifications include:
- Presumption of dependent or accessory personal security in case of unclear terminology (e.g. the use of “personal security on first demand”): any personal security is presumed to be a dependent or accessory personal security (i.e. an accessory and subsidiary guarantee), unless it can be proven otherwise.
- Statutory recognition of “personal security for all debts”, whose validity is now subject to the requirement that the guaranteed obligations be sufficiently determinable and that parties indicate the maximum guaranteed amount.
- Explicit confirmation of subsidiarity: the creditor must first serve notice on the principal debtor before calling upon the personal security, while notifying the provider of the personal security of such notice – thus settling a doctrinal debate.
- Introduction of statutory joint liability between multiple security providers of the same principal obligation: each security provider is liable within the limits of its commitment. This abolishes the benefit of division by default provided in the former Civil Code, which was often contractually excluded.
- Legal definition of “real personal security”, namely an act whereby a person grants a real security over their own property to guarantee the debt of another, while being liable only up to the value of the encumbered asset, without personal commitment.
- Legal definition of the autonomous guarantee: a guarantee that does not depend on the validity, terms and exitance of the principal obligation.
- Autonomous guarantees are non-transferable to another beneficiary.
- Merger of the personal security provider’s direct and sub rogatory rights of recourse following payment.
A specific section of Book 9, Title 1 significantly strengthens the protection of consumers (as defined by Article I.I.2° of the Economic Law Code) who provide personal securities. Personal security (cautionnement / borgtocht) becomes the only personal security that a consumer may grant. Any other personal security will be automatically requalified as a dependant or accessory personal security. Furthermore, other specific provisions apply for consumers providing a personal security, such as a mandatory contractual ceiling of that personal security.
The new provisions of Book 9 apply only to securities created after its entry into force on 1 January 2026, unless otherwise agreed.
In summary, Book 9, Title 1 of the new Civil Code strengthens legal certainty, aligns Belgian law with European standards, and introduces mandatory consumer protection, while preserving contractual freedom. Book 9 will in due course be completed by additional titles on pledge, mortgage, retention of title, right of retention, and privileges. These titles are currently under preparation.
Authors: Hervé Stanus & Ylenia Alonso Murciego
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