Cassazione establishes symmetry principle for mortgage usury calculations

The Italian Supreme Court (Cassazione), through its United Sections, has established a fundamental principle regarding the calculation of interest rates in usury litigation. The ruling mandates a principle of symmetry, requiring that both the contractual interest rate and the anti-usury threshold be calculated using the same methodology.

This decision addresses cases where lower courts had previously found mortgages to be usurious by applying different calculation methods to each side. Specifically, some courts had added the effect of compound interest (anatocism) from French amortization schedules to the contractual rate while comparing it against a threshold calculated via different criteria. The Court ruled that if an alternative method is used to calculate the contractual rate, the anti-usury threshold must also be recalculated using that same method to ensure a valid comparison.