Koro Villalonga
ADMINISTRATIVE LAW DIVISION
With its rulings issued on November 11, the Spanish Supreme Court has added another chapter to the long judicial history of mortgage clauses in consumer banking contracts.
Although some media outlets have attempted to promote the idea that this new decision opens a window of opportunity for claims, the truth is that the Supreme Court remains firm in its established case law—namely, the overall validity of IRPH clauses.
Before coming to this conclusion, which we have already anticipated, it is worth recalling that the clauses examined by the Supreme Court on this occasion are those that designate the IRPH as the reference index for calculating the variable interest rate of a mortgage loan.
Unlike the Euribor—used in most variable-rate mortgages—the Mortgage Loan Reference Index (IRPH) is calculated based on the simple average of the interest rates applied in the mortgage market over the previous three years. This very structure puts it at a disadvantage compared to other reference rates in the mortgage market (particularly the Euribor itself).
This circumstance, together with certain questionable banking practices that led to its inclusion in mortgage contracts, ultimately resulted in the IRPH being challenged before the courts. The dispute was partially addressed by the Court of Justice of the European Union (the “CJEU”) in its judgment of March 3, 2020 (C-125/2018), in which it concluded that the lawfulness of including this type of clause depended on passing the so-called “transparency control.” This essentially consists of verifying whether the consumer understood the clause’s inclusion in the mortgage contract. However, the “case-by-case” analysis imposed by the CJEU on national courts when assessing the clause’s abusive nature led to discrepancies in judicial evaluations—a matter that the Supreme Court has now settled with judgments No. 1590/2025 and 1591/2025, which we examine here.
Addressing the substance, the Supreme Court once again emphasizes that subjecting the variable interest rate to the IRPH is not null and void per se. Instead, it must be examined under the transparency control, which in this context means ensuring that the consumer had access to information about the index’s essential parameters (its composition, values, and historical evolution) and, specifically in this case, to Bank of Spain Circulars 5/1994 or 5/2012, depending on the contract’s date, where these parameters were sufficiently defined.
Thus, the Supreme Court reiterates that the IRPH clause is not inherently abusive and focuses the analysis on its transparency—something that is neither new nor does it signal the beginning of a new wave of consumer claims related to banking practices.
