Judgment of the Court (Ninth Chamber) of 11 June 2026 (request for a preliminary ruling from the Sąd Okręgowy w Warszawie – Poland) – DJ and PJ v Santander Bank Polska S.A.

(Case C-903/24,  (1) Zmarka  (2) )

(Reference for a preliminary ruling - Consumer protection - Directive 93/13/EEC - Unfair terms in consumer contracts - Article 6(1) and Article 7(1) - Loan agreement denominated in a foreign currency and containing unfair terms - Effects of the finding that a contractual term is unfair - Void agreement - Actions for restitution - Consumer’s right to default interest at the statutory rate on amounts to be repaid by the seller or supplier - National case-law requiring the payment of default interest at the statutory rate from the date on which the demand for payment was served indicating the specific amount of the claim - Dissuasive effect of the prohibition on unfair terms - Principle of effectiveness)

(C/2026/3971)

Language of the case: Polish

Referring court

Sąd Okręgowy w Warszawie

Parties to the main proceedings

Applicants: DJ and PJ

Defendant: Santander Bank Polska S.A.

Operative part of the judgment

Article 6(1) and Article 7(1) of Council Directive 93/13/EEC of 5 April 1993 on unfair terms in consumer contracts, read in the light of the principle of effectiveness,

must be interpreted as not precluding a judicial interpretation of national law according to which, following the annulment of a loan agreement concluded between a consumer and a seller or supplier, on the ground that that agreement cannot continue in existence after the removal of the unfair terms contained therein, that seller or supplier may be ordered to pay that consumer default interest at the statutory rate on the amount unduly paid by that consumer in the performance of that agreement only from the date on which that consumer notifies that seller or supplier of an extrajudicial document or a procedural document indicating the specific amount sought by the consumer.

---

(1)  OJ C, C/2025/1877.

(2)  The name of the present case is a fictitious name. It does not correspond to the real name of any party to the proceedings.