Tomasz Leśko and Weronika Magdziak-Śliwa from Kochański & Partners believe that the revolution expected by some will not happen and explain why.
On Thursday, February 12, the CJEU will answer the questions referred for a preliminary ruling by the District Court in Częstochowa (case C-471/24). This is an important moment for the predictability of economic turnover in Poland. The case concerns whether the WIBOR reference index, which is the basis for interest rates on a huge number of loan agreements, treasury bonds and business contracts, can be questioned in court. Supporters of this scenario completely ignore several important facts that undermine the sense of such actions. WIBOR is based on solid foundations – national and EU law. It is not an internal creation of banks, but an objective measure of the cost of money, administered by GPW Benchmark SA – a company subject to strict supervision and indirectly controlled by the State Treasury. Legal analysis and the current positions of the most important financial institutions indicate that there is only one likely scenario. WIBOR will remain the inviolable foundation of the Polish financial system.
See also: A sharp increase in lawsuits regarding WIBOR. Legal risk for banks is growing rapidly
Institutions defend the WIBOR indicator
The key argument in the debate on the legality of the indicator is the fact that WIBOR enjoys consistent support from the most important state bodies. The Financial Stability Committee and all its members: the Polish Financial Supervision Authority (KNF), the Ministry of Finance and the National Bank of Poland (NBP) consistently and jointly defend the correctness of determining this indicator – and its full compliance with the law.
Their positions so far clearly indicate that there are no legal or economic grounds to question this indicator. The voice of these institutions is of fundamental importance because they are responsible for the country's financial architecture.
The Polish Financial Supervision Authority, as the supervisory authority, confirms that the licensing process of the indicator administrator was rigorous and fully transparent.
The Ministry of Finance, in turn, points to the importance of WIBOR for the treasury debt market, and the National Bank of Poland emphasizes its role in monetary policy. Undermining the mechanism constructed in this way would mean not only an attack on the banking sector, but above all on the credibility of the entire state as a market regulator.
See also: The CJEU attacks WIBOR loans. Here are the consequences for customers [OPINIA]
Opinion of the CJEU spokesman. This is an announcement of the direction of the decision
An important signpost for the upcoming judgment is the opinion of the Advocate General of the CJEU, presented in September 2025. The spokeswoman clearly emphasized that there are no grounds to question WIBOR itself – because it is consistent with EU and national law, and the method of determining it has been accepted by the competent supervisory authority. Her opinion was a firm statement that EU law does not serve to question indicators that have been authorized under the BMR Regulation.
Therefore, all allegations regarding the WIBOR rate as such are groundless, since “such an examination falls outside the scope of Directive 93/13” — and finally “allowing national civil courts to review the method for setting critical benchmarks by assessing the unfairness of a contract term under Directive 93/13 would undermine the specific system for managing critical benchmarks established by the EU legislature under Regulation 2016/1011“. This is a quote from 69 points of opinion.
Going further, clauses referring to WIBOR can be controlled under European law (only)”if they are not formulated in plain and understandable language (transparency requirement)“. However, such detailed determinations (whether a given provision of the loan agreement is understandable to the consumer) are rightly left to the Polish courts for possible resolution – it is difficult to expect the CJEU to resolve a specific factual situation (although the recent, very numerous questions for a preliminary ruling from Poland may suggest that the domestic courts are counting on this).
See also: Who is right about the WIBOR dispute. Conflicting interpretations of the opinion coming from the CJEU
The information obligations of banks are specified in an EU regulation
It should also be noted that the Advocate General of the CJEU stated in her opinion that banks' information obligations regarding the use of benchmarks are detailed in the EU BMR Regulation.
According to these regulations, when concluding a loan agreement, the bank must inform the consumer about three key elements: the name of the benchmark used, the name of its administrator and the potential economic consequences for the consumer resulting from the use of this benchmark.
Contrary to voices appearing in the public debate, the spokeswoman clearly indicated that the bank is not obliged to inform the consumer about the detailed method of determining the reference index. The requirement of transparency does not mean that the bank is obliged to provide information that goes beyond the scope provided for in the BMR Regulation, and detailed data on the indicator methodology is made publicly available by its administrator.
Benchmark transparency
From the point of view of legal analysis, the foundation of WIBOR's security is its compliance with the EU BMR Regulation (i.e. Regulation 2016/1011 of June 8, 2016). It introduced strict standards for the process of determining the indicator value. Thus, from March 22, 2019, thanks to Commission Implementing Regulation 2019/482, WIBOR has the status of a “key benchmark indicator” pursuant to Art. 20 section 1.b) WMD. In short: is an indicator that plays a key role in the market of one of the Member States. This means, among other things, that a special legal regime applies to WIBOR, consisting of higher requirements, which must be met by both the administrator and the banks transmitting the data, and on greater powers of the Polish Financial Supervision Authority as a supervisory authority in relation to such an indicator. This indicator is also assessed periodically – once every two years.
Thanks to this, WIBOR is resistant to manipulation and independent of the decisions of a single bank. This transparency is a feature that completely distinguishes PLN loans from Swiss franc loans challenged in courts. In the case of Polish zlotys, the bank has no influence on the level of the index announced by GPW Benchmark, which excludes allegations of discretion in shaping the WIBOR rates.
Why are PLN loans not “new francs”?
We should clearly distance ourselves from attempts to compare potential disputes over WIBOR to the issue of foreign currency loans. In “franc” cases, the courts questioned the bank's unilateral right to set the currency rate. In the case of WIBOR, this situation does not occur. As noted, WIBOR is a reference index consistent with the BMR, and banks have no ability to influence the WIBOR level, and only an independent administrator under state supervision is responsible for the methodology and publication.
Representatives of the Polish Bank Association rightly point out that the bank cannot take responsibility for the development of interest rates — the amount of which is related to the WIBOR index — in the economy. The risk of changing interest rates is inherent in the nature of a variable rate loan, what customers about they were – and they are – after all informed before concluding the contract.
Banks also provided information on the name of the benchmark used and its administrator, and therefore fulfilled the information obligations set out in the opinion of the Advocate General. Consequently, assuming – in line with the current practice of the CJEU – that the future judgment will correspond to the content of this opinion, no change should be expected in the established jurisprudence of national courts, which remains favorable to banks.
Impact on the economy and citizens
The practical significance of the judgment, which will be announced on February 12, goes far beyond the relationships of banks with borrowers.
WIBOR is a key indicator of the Polish economy. On its basis, not only mortgage loans are valued, but also corporate bonds, financing of local government investments and savings products.
Any questioning of the stability of this indicator would affect the security of deposits of millions of Poles. The banking system must be based on predictability and respect for concluded contracts. Attempts to question professionally supervised market indicators are like opening Pandora's box – they are undoubtedly a threat to the capital market and will discourage investors from investing capital in Poland.
To sum up, the upcoming ruling of the Court of Justice of the European Union should be a voice of reason that will end the period of legal uncertainty. All final judgments issued so far in Poland in WIBOR cases, as well as expert opinions and clear positions of the Polish Financial Supervision Authority, the National Bank of Poland and the Ministry of Finance indicate that WIBOR is a legal, transparent and fully compliant with European standards.
The guarantee of market security is at stake
Confirmation of this fact by the Court will be an important guarantee of security for the entire Polish financial market — which did not go unnoticed by the Advocate General of the CJEU, who indicated at the beginning of her opinion that the case had “innovative character“since”In mortgage loans granted since 2013, the WIBOR rate is used as the reference index in 98.5 percent of cases. all loans granted to households in Poland. There is no doubt that this case is of particular importance for the Polish mortgage sector, especially to the extent that it uses the WIBOR rate.“.
Authors: Tomasz Leśko and Weronika Magdziak-Śliwa, partners in the law firm, Kochański & Partners
