The municipal property tax (Imposto Municipal sobre Imóveis), known as IMI, is an annual tax on property ownership calculated from the property’s taxable value, with the exact rate set by each municipality. For expats who own property, IMI is a recurring local cost that can vary by location and is often central to policy discussions about housing affordability.

The limitation period for most tax debts in Portugal is eight years (prescrição), with the start date depending on the tax type: from the tax event for taxes like IMT, from the end of the year in which the event occurred for IRS and IRC, or from the start of the following calendar year for withholdings. For expats this means tax authorities can assess or collect many debts for up to eight years after the triggering event, so it’s important to keep tax records for that period.