Banks can no longer manage interest rate risk through static assumptions and regulatory compliance alone. As rate volatility, digital banking, and faster-moving depositor behavior reshape the landscape, institutions are being pushed toward more dynamic IR
Banks must stop treating interest
rate risk as a standalone modeling exercise and instead embed it within a
broader balance sheet management framework if they are to navigate a
higher-for-longer rate environment successfully, senior industry leaders and supervisors
argued during a recent discussion on interest rate risk in the banking book.
The debate highlighted how sustained
rate volatility, evolving depositor behavior, digital banking, and diverging
regulatory expectations are forcing institutions to rethink long-established
assumptions about interest rate risk management.
Speaking at CeFPro's recent Risk
Evolve conference in London, a senior supervisor from a major European
regulatory authority said interest rate risk remains a unique challenge because
it sits largely within a Pillar 2 framework, creating significant scope for
supervisory judgment and model variation.
"We have strengthened our
methodology," said the supervisory executive, describing increased focus
on behavioral modeling, stress testing, governance frameworks, and hedging
strategies.
He noted that recent reviews have
paid particular attention to non-maturity deposit modeling and the lessons
learned from recent banking sector failures.
According to the regulator,
behavioral assumptions remain among the most important and challenging aspects
of interest rate risk management.
The supervisor explained that
institutions are increasingly being assessed on how effectively they model
customer behavior, deposit stability, and responses to changing interest rate
environments. Credit spread risk in the banking book has also emerged as an
area receiving increased supervisory attention.
A prudential risk leader from a major
UK banking group argued that banks need a much broader perspective than
interest rate scenarios alone.
"A framework for interest rate
modelling and IRRBB modelling cannot be done in isolation just through interest
rates," he said.
Instead, he advocated what he
described as a conscious balance sheet management framework in which balance
sheet behavior is modeled through customer, market, and macroeconomic drivers
simultaneously.
The executive suggested that
understanding customer behavior is increasingly central to managing interest
rate risk, particularly as institutions attempt to distinguish between stable
and volatile deposits and anticipate future balance sheet movements.
A treasury risk director from a major
global custody bank highlighted another growing challenge: regulatory
divergence.
From an industry perspective, he
argued that differing approaches between European, UK, and US regulators are
creating significant complexity for internationally active banks.
"The divergence across
jurisdictions when you're managing internationally" has become one of the
industry's biggest operational challenges, he said.
The executive pointed to differences
in supervisory shocks, earnings metrics, and customer behavior assumptions, all
of which can result in different interpretations of risk across jurisdictions.
As a consequence, senior management
teams often face multiple versions of the same risk metric, each calculated
using slightly different assumptions and regulatory requirements.
