Central Bank of Iceland expands mortgage debt service ratio calculation and issues new oversight and incident response rules for systemically important financial market infrastructure

The Central Bank of Iceland has amended its Rules on Maximum Debt Service-to-Income Ratios for Mortgage Loans to Consumers and adopted two new rulebooks covering oversight of systemically important financial market infrastructure and a financial infrastructure incident centre. The package was approved by the Financial Stability Committee at its 1 to 2 December meeting. For consumer mortgages, the amended debt service calculation must include all payments accruing to individuals for the acquisition of residential property. Where an individual co-owns a residence with an entity that owns or retains a holding for commercial purposes, the individual’s payments to that entity for use of its share must be included in the debt service assessment, regardless of when the payments are remitted. The revised mortgage rules will be reissued under the current title, published in Stjórnartíðindi later the same day, and take effect on 4 December 2025. The new infrastructure oversight rules set criteria for designating systemically important components whose activities could affect financial stability and outline how the Bank will oversee their operational frameworks, distinguishing between critical infrastructure and core infrastructure. The incident centre rules define the centre’s role and its participants, with a focus on rapid, secure information exchange and coordinated responses to cyber and operational incidents. The Bank plans to publish the two new infrastructure rulebooks in Stjórnartíðindi within a few days; they will take effect on the day after publication.