Annual disclosure regarding the designation of and capital buffers on Belgian O-SIIs (1 December 2025)

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Annual disclosure concerning the identification of Belgian systemically important institutions and determination of the additional capital requirements to which they are subject (1 December 2025) In its capacity as the macroprudential authority, the National Bank of Belgium (NBB) undertakes an annual assessment to identify the Belgian banks that should be designated as domestic systemically important institutions (“other systemically important institutions” or O-SIIs in EU legislation). The NBB’s Board of Directors has completed this assessment for 2025 and determined the additional capital requirements to be imposed on the identified institutions. Systemically important banks are institutions whose failure would have a significant impact on the financial system or the real economy. The NBB imposes additional capital requirements on such banks for two reasons: (1) to reduce the likelihood of their default, given the high economic and social costs such an event would entail, and (2) to ensure they have a capital buffer that sufficiently reflects the negative externalities that would be generated by their failure. O-SII identification In 2025, the NBB again updated the list of O-SIIs based on the methodology laid out in the European Banking Authority (EBA) Guidelines on the identification of O-SIIs. 1 This methodology consists of two steps: the first involves the automatic designation of O-SIIs on the basis of a scoring process while the second allows the macroprudential authority to exercise supervisory judgment to determine whether further entities should be designated as O-SIIs. In the first step, a score is attributed to each institution to match its systemic importance, using quantitative criteria based on one or more mandatory indicators concerning the size, substitutability (the ability of other institutions to rapidly take over any critical services provided by the bank), complexity and interconnectedness of the institution. The score per indicator received by each institution reflects its share in the total value for all Belgian banks and thus, in a sense, represents its market share. The overall score of an institution is calculated as the weighted average of its scores for each indicator. Any institution with an overall score above a given threshold value is automatically designated as an O-SII. The indicators and their respective weighting in the overall score are as follows:
Criterion Indicator Weight
Size Total assets 25.00%
Importance (including substitutability/financial system infrastructure) Value of domestic payment transactions 8.33% Private sector deposits from depositors in the EU 8.33% Private sector loans to recipients in the EU 8.33% Complexity/cross-border activity Value of OTC derivatives (notional) 8.33% Cross-jurisdictional liabilities 8.33% Cross-jurisdictional claims 8.33% Interconnectedness Intra-financial system liabilities 8.33% Intra-financial system assets 8.33% Debt securities outstanding 8.33% 1 EBA Guidelines EBA/GL/2014/10 of 16 December 2014 on the criteria to determine the conditions of application of Article 131(3) of Directive 2013/36/EU (CRD) in relation to the assessment of other systemically important institutions (O-SIIs).

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In the second step of the methodology, the macroprudential authority may assess whether additional institutions should be designated as O-SIIs. To do so, it may make use of other indicators or give different weightings to the mandatory indicators. Pursuant to this methodology, the NBB has reconfirmed the identification as O-SIIs of the eight Belgian banks designated as systemically important in 2024. These are BNP Paribas Fortis, KBC Group, Euroclear Holding, ING Belgium, Belfius Bank, The Bank of New York Mellon, Investeringsmaatschappij Argenta, and Crelan. The first seven of these banks automatically qualify as O-SIIs in view of their scores under the first step of the EBA methodology. Crelan, by contrast, was designated as an O-SII in the second step, on the basis of supervisory judgment. The scores that these eight institutions obtained in the first step of the methodology are provided below. Institutions with a score above a threshold of 325 basis points are automatically designated as O-SIIs. Institution O-SII score (2025) O-SII score (2024) BNP Paribas Fortis 2380 2400 KBC Group 2343 2450 Euroclear Holding 1725 1587 ING Belgium 1149 1229 Belfius Bank 1074 1104 The Bank of New York Mellon 418 379 Investeringsmaatschappij Argenta 338 359 Crelan 290 305 The alternative indicators considered in the second step of the methodology were: (1) private sector deposits from depositors in Belgium; (2) private sector loans to recipients in Belgium; (3) liabilities with respect to the Belgian financial sector; and (4) assets with respect to the Belgian financial sector. As the scope of these indicators is domestic, they are considered more appropriate for identifying domestic systemically important institutions than some of the indicators with a European or global scope used in the first step. On the basis of these alternative indicators, Crelan was designated as an O-SII, having received an alternative score above the threshold of 325 basis points. O-SII buffers As the failure of larger, more systemically important institutions would give rise to disproportionate social costs, additional common equity tier 1 (CET1) capital requirements are imposed on such institutions. This means that their capital requirements increase proportionally more than their risk￾weighted assets. For all eight O-SIIs, the NBB’s Board of Directors decided to maintain the additional CET1 capital buffer announced in 2023. 2 Such additional requirements are imposed on the basis of Article 14 of
Annex IV to the Belgian Banking Act.3 Several criteria are taken into account to calibrate the O-SII
buffers, including historical losses in the Belgian banking sector, the results of stress tests, and the need to ensure a level playing field in relation to O-SIIs in other EU jurisdictions as regards O-SII buffer rates and total capital requirements. The degree of systemic importance of the bank concerned, as determined by its size and its O-SII score, is also considered: less systemically 2 NBB Regulation of 12 April 2022 determining the method for designating domestic systemically important institutions and for setting the level of their CET1 capital buffer, as amended by the NBB Regulation of 13 June 2023. 3 Act of 25 April 2014 on the legal status and supervision of credit institutions (Belgian Banking Act).

NBB - Public important institutions are required to maintain a 0.75% buffer, while more systemically important institutions are required to maintain a 1.5% buffer. 4 Institution O-SII buffer rate BNP Paribas Fortis 1.5% KBC Group 1.5% Euroclear Holding 1.5% ING Belgium 1.5% Belfius Bank 1.5% The Bank of New York Mellon 0.75% Investeringsmaatschappij Argenta 0.75% Crelan 0.75% The O-SII buffers are primarily structural in nature. In the event of a persistent crisis and should the need for additional support measures arise, they can be released temporarily, after coordination with the national and international authorities concerned. The release of these buffers would probably be one of the last macroprudential tools to be used. 4 Without prejudice to the caps laid down in Article 14 §5 of Annex IV to the Belgian Banking Act.