Provisional text
JUDGMENT OF THE COURT (Ninth Chamber)
16 April 2026 (*)
( Reference for a preliminary ruling – Consumer protection – Directive 93/13/EEC – Unfair terms in consumer contracts – Effects of a term being found to be unfair – Invalidity of the loan agreement – Actions for restitution – Limitation period for the action brought by the seller or supplier – Interruption of the limitation period – Principle of effectiveness – Principle of legal certainty – Principle of proportionality – Right of access to a court – Unjust enrichment )
In Case C‑752/24 [Jangielak], (i)
REQUEST for a preliminary ruling under Article 267 TFEU from the Sąd Okręgowy w Warszawie (Regional Court, Warsaw, Poland), made by decision of 30 October 2024, received at the Court on the same date, in the proceedings
mBank S.A.
v
KŁ,
JŁ,
THE COURT (Ninth Chamber),
composed of M. Condinanzi, President of the Chamber, R. Frendo (Rapporteur) and A. Kornezov, Judges,
Advocate General: R. Norkus,
Registrar: A. Calot Escobar,
having regard to the written procedure,
after considering the observations submitted on behalf of:
–        mBank S.A., by A. Cudna-Wagner, radca prawny, and B. Miąskiewicz, adwokat,
–        KŁ and JŁ, by I. Gabrysiak and J. Kmieć, adwokaci,
–        the Polish Government, by B. Majczyna, acting as Agent,
–        the Portuguese Government, by A. Pimenta and A. Rodrigues, acting as Agents,
–        the European Commission, by P. Kienapfel and B. Sasinowska, acting as Agents,
having decided, after hearing the Advocate General, to proceed to judgment without an Opinion,
gives the following
Judgment
1        This request for a preliminary ruling concerns the interpretation of Article 7(1) of Council Directive 93/13/EEC of 5 April 1993 on unfair terms in consumer contracts (OJ 1993 L 95, p. 29), as well as the principles of effectiveness, proportionality, legal certainty and the right of access to a court.
2        The request has been made in proceedings between, on the one hand, mBank S.A., a banking institution, and, on the other hand, KŁ and JŁ, two consumers, concerning the recovery of a debt resulting from the invalidity of a mortgage loan agreement on account of unfair terms contained therein.
Legal context
European Union law
3        Article 6(1) of Directive 93/13 provides:
‘Member States shall lay down that unfair terms used in a contract concluded with a consumer by a seller or supplier shall, as provided for under their national law, not be binding on the consumer and that the contract shall continue to bind the parties upon those terms if it is capable of continuing in existence without the unfair terms.’
4        Article 7(1) of that directive provides:
‘Member States shall ensure that, in the interests of consumers and of competitors, adequate and effective means exist to prevent the continued use of unfair terms in contracts concluded with consumers by sellers or suppliers.’
Polish law
5        Article 58(1) of the ustawa – Kodeks cywilny (Law establishing the Civil Code) of 23 April 1964 (Dz. U. of 2024, item 1061), in the version applicable to the dispute in the main proceedings (‘the Civil Code’), provides:
‘A legal act that is contrary to the law or intended to circumvent the law shall be null and void, unless a relevant provision provides otherwise, in particular where it provides that the invalid terms of the legal act in question are to be substituted by relevant provisions of law.’
6        Article 118 of that code provides:
‘Unless a specific provision provides otherwise, the limitation period shall be six years, and for claims concerning periodic payments, as well as claims related to the pursuit of a business activity, it shall be three years. However, the limitation period shall expire on the last day of the calendar year, unless it is shorter than two years.’
7        Article 123(1)(1) of that code provides:
‘The limitation period shall be interrupted:
1.      by any act before a court of law or another body appointed to try cases or to enforce claims of a given kind or before an arbitration court, which is undertaken directly to pursue, to establish, to satisfy or to secure a claim’.
8        Under Article 124(1) and (2) of the Civil Code:
‘1.      Each interruption shall start time running afresh.
2.      If the limitation period is interrupted by an act in the course of proceedings before a court of law or another body appointed to try cases or to enforce claims of a given kind or before an arbitration court, the limitation period shall not begin to run afresh until the proceedings are over.’
9        Article 3851(1) and (2) of the Civil Code provides as follows:
‘1.      The terms of a contract concluded with a consumer which have not been individually negotiated shall not be binding on the consumer if his or her rights and obligations are set forth in a way that is contrary to the accepted principles of morality and seriously infringes his or her interests (unlawful terms). This provision shall not apply to terms setting out the parties’ main obligations, including price or remuneration, so long as they are worded clearly.
2.      If a contractual term is not binding on the consumer pursuant to paragraph 1, the contract shall otherwise continue to be binding on the parties.’
10      Article 405 of that code provides:
‘Any person who, without legal grounds, obtains an economic advantage at the expense of another person shall be required to restore that benefit in kind and, where that is not possible, to return the value thereof.’
11      According to Article 410(1) and (2) of that code:
‘1.      The provisions of the preceding articles shall apply in particular to undue performance.
2.      A performance shall be undue if the person who rendered it was not under any obligation at all or was not under any obligation towards the person to whom he or she rendered the performance, or if the basis for the performance has ceased to exist or if the intended purpose of the performance has not been achieved, or if the legal act on which the obligation to render the performance was based was invalid and has not become valid since the performance was rendered.’
The dispute in the main proceedings and the question referred for a preliminary ruling
12      In September 2008, KŁ and JŁ entered into a loan agreement indexed to the Swiss franc (CHF) with mBank. Pursuant to that agreement,
the latter paid them the sum of 226 000 zlotys (PLN) (approximately EUR 53 000).
13      Being of the view that that agreement contained unfair terms, the two consumers sought to have that loan agreement declared invalid, in the context of a collective action brought before the Sąd Okręgowy w Łodzi (Regional Court, Łódź, Poland), by a procedural document served on mBank on 28 September 2017. The composition of the group which KŁ and JŁ joined was established by order of the Sąd Okręgowy w Łodz (Regional Court, Łódź) on 13 March 2018.
14      On 13 December 2021, mBank brought an action against KŁ et JŁ before the Sąd Okręgowy w Warszawie (Regional Court, Warsaw, Poland), which is the referring court. mBank asks that, in the event that the loan agreement is declared invalid at the end of the collective action, the consumers be ordered to repay to it, on the basis of Article 405 of the Civil Code, read in conjunction with Article 410(1) thereof, the principal amount of the loan, together with default interest at the statutory rate.
15      KŁ and JŁ contend that the action should be dismissed, arguing, in particular, that mBank’s claim is time-barred. They note that mBank seeks an order requiring them to pay that claim in the event that the credit agreement is declared invalid in the context of the collective action, and that, therefore, it is not directly asserting its claim before the court hearing the matter. As a result, the bringing of mBank’s action does not have the effect of interrupting the limitation period for its claim within the meaning of Article 123(1) of the Civil Code.
16      The referring court notes that the existence of mBank’s claim, in itself, is not in doubt, but that, in order to resolve the dispute in the main proceedings, it is necessary to determine whether the limitation period for that claim was in fact interrupted by the bringing of mBank’s action for restitution.
17      In that regard, the referring court explains that, according to the case-law of the Sąd Najwyższy (Supreme Court, Poland), the three-year limitation period for a seller or supplier’s claim starts to run on the date the consumer first contested, before that seller or supplier, the binding nature of the contractual terms. In the present case, that is the date the Sąd Okręgowy w Łodzi (Regional Court, Łódź) issued the order determining the composition of the group in the collective action against mBank, namely 13 March 2018.
18      Accordingly, if the bringing of mBank’s action for restitution on 13 December 2021 can be regarded as a ground for interruption of the limitation period within the meaning of Article 123(1)(1) of the Civil Code, mBank’s claim would not be time-barred within the meaning of Article 118 of the Civil Code. Conversely, if, as KŁ and JŁ argue, the bringing of that action did not validly interrupt the limitation period, mBank’s claim would now be time-barred.
19      The referring court notes that, in the context of the collective proceedings, mBank argues that the loan agreement at issue does not contain any unfair terms, so that the action seeking to have it declared invalid should be dismissed. However, in the case in the main proceedings, mBank seeks an order requiring the consumers to repay the loan capital, together with default interest, in the event that that agreement is declared invalid, while knowing that that question will be decided in the context of the collective action to which those consumers are parties.
20      In those circumstances, the referring court is uncertain whether Article 7(1) of Directive 93/13 precludes the bringing of the bank’s action for restitution from interrupting the limitation period for the bank’s claim.
21      It observes that, on the one hand, that claim gives rise to a situation of uncertainty for the consumer, who is compelled to defend him or herself against it, while having an interest in accepting it and repaying the principal of the loan without delay, in order to avoid being ordered to pay interest and costs should the application for the credit agreement to be declared invalid be dismissed in the collective action.
22      On the other hand, the referring court is of the view that mBank’s conduct is justified by the need to interrupt the limitation period for its claim before the collective action concludes, since that period began to run on 13 March 2018. That seller or supplier cannot be deprived of the possibility of effectively asserting its claim and, as a result, of its right of access to a court. According to the referring court, such a significant restriction on the procedural rights of the seller or supplier in question could go beyond the objective of consumer protection and, as a result, infringe the principle of proportionality.
23      In addition, the principle of legal certainty requires a uniform interpretation of Article 123(1)(1) of the Civil Code in all circumstances, to the effect that the submission of an application for performance of an obligation interrupts, in any event, the limitation period.
24      In those circumstances, the Sąd Okręgowy w Warszawie (Regional Court, Warsaw) decided to stay the proceedings and to refer the following question to the Court of Justice for a preliminary ruling:
‘Must Article 7(1) of Council Directive [93/13], and the principles of effectiveness, proportionality, legal certainty and of the right of access to a court or tribunal, be interpreted as precluding a judicial interpretation of national legislation according to which the limitation period for a seller or supplier’s claim against a consumer for the return of undue payments [made] under the contract, which has become null and void because it contains unfair terms, is interrupted by an action for payment brought by the bank before the definitive conclusion of proceedings brought earlier by the consumer for a declaration that the loan contract is null and void?’
Consideration of the question referred
Admissibility
25      KŁ and JŁ, as well as the Polish Government, argue that, contrary to what is stated in the order for reference, according to national case-law, the limitation period for mBank’s claim began to run on the date on which the application for the loan agreement to be declared invalid in the context of the collective action was served on mBank, namely 28 September 2017. Therefore, the claim which is the subject of the dispute in the main proceedings was already time-barred when that bank’s claim for repayment was lodged, with the result that the question referred is hypothetical and thus inadmissible.
26      In that regard, it is sufficient to note that, in accordance with settled case-law, the Court must take into account, under the division of jurisdiction between the Courts of the European Union and national courts, the factual and legal context, as set out in the order for reference, of the questions referred for a preliminary ruling, which means that a reference for a preliminary ruling cannot be examined in the light of the interpretation of national law relied on by the government of a Member State or a party to the main proceedings (judgment of 21 December 2021, Trapeza Peiraios, C‑243/20, EU:C:2021:1045, paragraph 53 and the case-law cited).
27      In the present case, it is apparent from the order for reference that the referring court considers that, under the national rules, the limitation period for mBank’s claim runs from the date on which, in the context of the collective action, the order establishing the composition of the group joined by KŁ and JŁ was issued, namely 13 March 2018, and that, therefore, mBank’s claim was not yet time-barred on the date mBank lodged its action for restitution, namely 13 December 2021.
28      In those circumstances, the question referred is not hypothetical and is, therefore, admissible.
Substance
29      By its question, the referring court asks, in essence, whether Article 7(1) of Directive 93/13 and the principle of effectiveness, having regard to the right of access to a court and the principles of proportionality and legal certainty, must be interpreted as precluding a judicial interpretation of a provision of national law according to which the bringing by a seller or supplier of an action for restitution of the payments made in connection with a credit agreement, which is the subject of separate proceedings brought by the consumer seeking the invalidation of that agreement on account of unfair terms contained therein, interrupts the limitation period for that seller or supplier’s claim, before the definitive conclusion of those proceedings.
30      That court notes that, first, the three-year limitation period for mBank’s right to rely on the restitutory effects of the invalidation of the loan agreement would, as a result of mBank’s inaction, have expired before delivery of the decision on the application for invalidation of that agreement, brought by the consumers. Second, the bringing of mBank’s action for restitution obliges the consumers to defend themselves, even though mBank, in the context of those invalidity proceedings, which are still pending, contends that that contract is valid.
31      In that regard, it should be borne in mind, first of all, that Article 7(1) of Directive 93/13 requires the Member States to ensure that, in their national legal systems, adequate and effective means exist to prevent the continued use of unfair terms in contracts concluded with consumers by sellers or suppliers.
32      Next, according to settled case-law, a contractual term held to be unfair must be regarded, in principle, as never having existed, so that it cannot have any effect on the consumer. Therefore, the determination by a court that such a term is unfair must, in principle, have the consequence of restoring the consumer to the legal and factual situation that he or she would have been in if that term had not existed by, inter alia, creating a right to restitution of advantages wrongly obtained, to the consumer’s detriment, by the seller or supplier on the basis of that unfair term (judgment of 15 June 2023, Bank M. (Consequences of the annulment of the contract), C‑520/21, EU:C:2023:478, paragraph 65 and the case-law cited). This is the case also where the unfair nature of one or more terms in a contract concluded between a consumer and a seller or supplier results not only in the nullity of those terms, but also in the invalidity of the contract in its entirety (see, to that effect, judgment of 15 June 2023, Bank M. (Consequences of the annulment of the contract), C‑520/21, EU:C:2023:478, paragraph 66 and the case-law cited).
33      That objective of restoring the consumer’s legal and factual situation to what it would have been in the absence of one or more unfair terms must be pursued in a manner that complies with the principle of proportionality, a general principle of EU law, which requires that the national legislation implementing that law must not go beyond what is necessary to attain the objective pursued (judgment of 23 November 2023, Provident Polska, C‑321/22, EU:C:2023:911, paragraph 85 and the case-law cited).
34      That principle of proportionality would be infringed if restitutio in integrum were to be excluded in respect of the seller or supplier. Accordingly, the obligation to restore the parties to their original position, following the invalidation of a loan agreement containing unfair terms, must be mutual; the bank may not, however, seek compensation from the consumer going beyond reimbursement of the capital paid in respect of the performance of that agreement together with the payment of default interest at the statutory rate from the date on which notice is served (see, to that effect, judgment of 7 December 2023, mBank (Consumer declaration), C‑140/22, EU:C:2023:965, paragraph 62 and the case-law cited).
35      Furthermore, the restitutory effect attached to the invalidation of a loan agreement containing unfair terms, which also justifies the bank’s action for restitution, ensures that the protection of the rights guaranteed by the legal order of the European Union does not entail the unjust enrichment of the consumer (see, by analogy, judgment of 13 July 2006, Manfredi and Others, C‑295/04 to C‑298/04, EU:C:2006:461, paragraph 94).
36      Lastly, it is important to bear in mind that, in accordance with the case-law, the principle of equality of arms, which is a corollary of the very concept of a fair trial and aims to ensure a balance between the parties to the proceedings, implies that each party must be afforded a reasonable opportunity to present its case under conditions that do not place it at a substantial disadvantage vis-à-vis its opponent (judgment of 28 July 2016, Ordre des barreaux francophones et germanophone and Others, C‑543/14, EU:C:2016:605, paragraph 40 and the case-law cited), including, in the present case, by the seller or supplier bringing an action for restitution, which is separate from parallel proceedings concerning the invalidity of a loan agreement containing unfair terms,
to interrupt the limitation period for its claim.
37      The submission of such a claim not only does not, in principle, interfere with the exercise, by the consumers, of their right to restitution of advantages wrongly obtained by that seller or supplier on the basis of unfair terms, but it also contributes to restoring the legal and factual situation which those consumers would have been in in the absence of those terms.
38      Moreover, according to the Court’s settled case-law, the principle of legal certainty, to which the referring court also makes reference, is aimed at ensuring foreseeability of situations and legal relations (judgment of 16 October 2019, Agrárminiszter, C‑490/18, EU:C:2019:863, paragraph 35 and the case-law cited). Therefore, that principle does not preclude a rule of national law, such as Article 123(1)(1) of the Civil Code, under which the bringing of an action for performance of an obligation interrupts, in all circumstances, the limitation period for the right to that performance.
39      That said, the referring court notes that, in the event that the limitation period for the seller or supplier’s claim is interrupted by means of the bringing by that seller or supplier of a separate action for restitution before the definitive conclusion of the proceedings concerning the application for a declaration of invalidity, brought earlier by the consumers before another court, the consumers would be obliged to lodge a defence and, if they are unsuccessful in the proceedings, to pay default interest and costs in the proceedings brought by that seller or supplier.
40      As regards the limitation period applicable to the seller or supplier’s claim for restitution, it should be noted that, in accordance with settled case-law, in the absence of specific EU legislation on the subject, the detailed rules for implementing the consumer protection provided for by Directive 93/13 are a matter for the domestic legal order of the Member States by virtue of the principle of their procedural autonomy. However, those rules must not be less favourable than those governing similar domestic actions (principle of equivalence), nor may they be framed in such a way as to make it in practice impossible or excessively difficult to exercise the rights conferred by EU law (principle of effectiveness) (judgment of 14 December 2023, Getin Noble Bank (Limitation period for actions for restitution), C‑28/22, EU:C:2023:992, paragraph 60 and the case-law cited).
41      In that regard, the Court has already held that procedural arrangements which give rise to overly high costs for the consumer could have the effect of deterring that consumer from properly defending his or her rights before the court before which proceedings have been brought by the seller or supplier (see, to that effect, judgment of 7 April 2022, Caixabank, C‑385/20, EU:C:2022:278, paragraph 54).
42      It is therefore for the referring court to apply, as far as possible, national law, including procedural rules allowing, where appropriate, the proceedings relating to the seller or supplier’s action for restitution to be stayed pending the final resolution of the proceedings relating to the application for the loan agreement to be declared invalid brought earlier by the consumers, so that the consequences which, under that law, result from mBank’s interruption of the limitation period for its claim before the loan agreement is declared invalid on account of the unfair terms contained therein do not undermine Directive 93/13’s objective of ensuring a high level of consumer protection. That court must also ensure that the costs incurred in the action for restitution brought by the bank before the invalidation of the contract, and which the consumers must pay if they are unsuccessful in that action, are not disproportionately high so that consumers are deterred from asserting their rights under that directive.
43      As regards the fact, pointed out by the referring court, that the consumer would be obliged to lodge a defence in the proceedings relating to the action for restitution brought by the seller or supplier, it should be noted that that fact alone, which seeks, moreover, to uphold the adversarial principle, is not such as to make it in practice impossible or excessively difficult to exercise the rights conferred on the consumer by EU law.
44      In the light of the foregoing, the answer to the question referred is that Article 7(1) of Directive 93/13 and the principle of effectiveness, having regard to the right of access to a court and the principles of proportionality and legal certainty, must be interpreted as not precluding, in principle, a judicial interpretation of a provision of national law according to which the bringing by a seller or supplier of an action for restitution of the payments made in connection with a credit agreement, which is the subject of separate proceedings brought by the consumer seeking the invalidation of that agreement on account of unfair terms contained therein, interrupts the limitation period for that seller or supplier’s claim, before the definitive conclusion of the latter proceedings, provided that the national court, while taking into account all of the national law, takes all the measures necessary to ensure that exercise of the rights which the consumer derives from Directive 93/13 is not rendered excessively difficult or impossible.
Costs
45      Since these proceedings are, for the parties to the main proceedings, a step in the action pending before the referring court, the decision on costs is a matter for that court. Costs incurred in submitting observations to the Court, other than the costs of those parties, are not recoverable.
On those grounds, the Court (Ninth Chamber) hereby rules:
Article 7(1) of Council Directive 93/13/EEC of 5 April 1993 on unfair terms in consumer contracts, and the principle of effectiveness, having regard to the right of access to a court and the principles of proportionality and legal certainty,
must be interpreted as not precluding, in principle, a judicial interpretation of a provision of national law according to which the bringing by a seller or supplier of an action for restitution of the payments made in connection with a credit agreement, which is the subject of separate proceedings brought by the consumer seeking the invalidation of that agreement on account of unfair terms contained therein, interrupts the limitation period for that seller or supplier’s claim, before the definitive conclusion of the latter proceedings, provided that the national court, while taking into account all of the national law, takes all the measures necessary to ensure that exercise of the rights which the consumer derives from Directive 93/13 is not rendered excessively difficult or impossible.
[Signatures]
*      Language of the case: Polish.
i      The name of the present case is a fictitious name. It does not correspond to the real name of any party to the proceedings.