In a judgment rendered on 11 December 2025 in case C-767/24 [Kuszycka], the Court of Justice of the European Union (CJEU) strengthens consumer protection by neutralising a national procedural formalism deemed incompatible with Directive 93/13/EEC. The Court holds that the principle of effectiveness precludes a situation where the submission of a set-off declaration by a consumer automatically results in the loss of their right to invoke the limitation period against the bank.
CJEU, 11 December 2025, No. C-767/24, Kuszycka
I. Background of the dispute: the annulment of a foreign currency-indexed loan
The case originated in Poland, where a consumer, ML, had entered into a mortgage loan agreement denominated in Swiss francs (CHF) with mBank. Having identified the presence of unfair terms, the referring court held that the contract could not survive and had to be declared void.
In this context of nullity, the parties are required to make mutual restitution: the bank claims the capital disbursed, while the consumer seeks reimbursement of the instalments paid. However, a major procedural difficulty arose:
- The bank’s claim was time-barred under national law at the time of the action.
- The consumer raised this limitation defence, while simultaneously submitting a set-off declaration as a defence.
II. The conflict between national case law and the principle of effectiveness
The difficulty lay in the application of established Polish case law. According to this interpretation, set-off “constitutes a waiver of the limitation defence” because it amounts to an implicit acknowledgement of the debt.
The CJEU firmly rejects this automatic approach in the name of the principle of effectiveness. It reiterates that national procedural rules must not be arranged in such a way as to render “practically impossible or excessively difficult the exercise of the rights” conferred by Union law.
The Court develops three cardinal arguments:
- Hindrance to procedural rights: Limiting the limitation defence to abstention from set-off “amounts, in reality, to limiting the consumer’s ability to exercise a procedural right provided for by national legislation”.
- Weakening of the deterrent effect: Such a rule would allow the professional to recover a time-barred claim and thus “derive an advantage from its own unlawful conduct” which gave rise to the annulment of the contract.
- Absence of clear intent: The Court emphasises that a waiver cannot be presumed, particularly when the consumer “expressly manifests the contrary intention to rely on the limitation period” through a simultaneous act.
« Une jurisprudence nationale qui déduit une renonciation implicite à l’exception de prescription de la seule présentation d’une déclaration de compensation, sans vérification de la volonté du consommateur, méconnaît cette exigence. »
III. Consequences for national law and professionals
This judgment imposes on national courts an obligation of consistent interpretation. If they cannot interpret domestic law in accordance with these requirements, they must “if necessary, disapply of their own authority the national case law at issue“.
1. The end of the automatic “acknowledgement of debt” presumption
For pending disputes, the court can no longer infer an implicit waiver from the mere fact of a procedural act such as set-off. The consumer may now maintain a coherent “multi-layered” defence: challenging the validity of the contract, invoking the limitation of the bank’s claim, and requesting set-off on a subsidiary basis.
2. The reinforcement of the asymmetry of limitation periods
This judgment accentuates an already marked imbalance in favour of the consumer regarding time limits:
- Imprescriptibility for the consumer: The action seeking to have an unfair term declared unwritten (void) is often imprescriptible under many national laws.
- Strictness for the professional: Banks must be extremely vigilant in managing their recovery deadlines. They can no longer hope to “salvage” a time-barred claim through a procedural misstep by the consumer.
3. The increased duties of the national court
The court becomes the guarantor of contractual balance and must:
- Objectively inform the consumer of the legal consequences of the removal of unfair terms.
- Verify whether any purported waiver of the limitation defence is genuinely voluntary and informed, even where the consumer is represented by a lawyer.
- Set aside of its own motion any national case law that is incompatible with these European requirements.
Conclusion
The Kuszycka judgment confirms that national rules of civil procedure must not become an obstacle to the substantive protection afforded by Union law. For banking institutions, this decision requires a review of litigation strategies, as it definitively secures the consumer’s right to use all available defence mechanisms without risking the loss of the benefit of the limitation period.
This decision is perceived as “severe” for bankers, but logical in order to ensure the balance of power. Lending institutions must henceforth exercise increased vigilance in managing their recovery deadlines in disputes involving unfair terms.
