EU Banks Lose Internal Credit Risk Models, Hit Capital

European Union banks that for years used proprietary credit risk models to calculate capital requirements are losing that freedom. Regulators have been tightening the rules around internal ratings-based (IRB) approaches, pushing lenders toward standardised regulator-set metrics. The shift, which has been building for several years, now looks decisive.

Banks that relied on IRB models generally held less capital against loans than the standardised approach would require. Deutsche Bank, BNP Paribas and UBS all use IRB for some portfolios. Under standardised rules, risk weights for corporate and retail lending rise, meaning more capital must be set aside for the same loan book. That directly hits return on equity, a metric investors watch closely.

The European Banking Authority has led the push. Its 2023 guidelines restricted the use of IRB for low-default portfolios and set tighter criteria for model approval. The European Commission’s proposed amendments to the Capital Requirements Regulation go further, limiting IRB for certain asset classes and forcing banks to calculate capital floors based on the standardised approach. The Basel III endgame, already adopted in the EU, reinforces the same direction: internal models get less room, standardised metrics get more.

Timing matters. The first set of binding constraints will hit in 2025, when the output floor–a rule that prevents internal models from producing capital charges lower than 72.5% of the standardised calculation–takes full effect. That floor alone will raise capital requirements for some large EU lenders by 10–20% on risk-weighted assets, according to industry estimates. Banks that had the biggest gaps between internal and standardised numbers will feel the squeeze first.

Not everyone sees this as a loss. The IRB approach had become opaque, with banks’ models producing wildly different capital outcomes for similar loans. Standardisation may improve comparability across lenders and reduce the risk of regulatory arbitrage. Even some former supporters of internal models now say the system needed a reset. The argument is that simplicity and consistency outweigh the precision internal models once promised.

For equity holders, the implications are concrete. Higher capital requirements mean lower leverage, which pressures earnings per share and dividend payouts. Banks may try to offset the hit by cutting costs, shuttering low-margin businesses or passing costs to borrowers through wider loan spreads. Those moves are slow and uncertain. The market’s reaction so far has been muted–European bank stocks have not sold off sharply on the IRB changes–but the full cost will crystallise as 2025 compliance deadlines approach.

What could reduce the risk: a compromise by regulators on the output floor’s calibration, or a sustained recovery in net interest margins that absorbs the extra capital cost. What would worsen it: a recession that raises credit losses and pushes risk weights higher under the standardised formula, creating a double hit.

The final regulatory text is expected before year-end. Banks are already submitting transition plans. For shareholders, the era of model-driven capital optimisation is closing.