Imposto Municipal sobre as Transmissões Onerosas de Imóveis·Municipal property transfer tax·IMT
IMT is the municipal tax on transfers of ownership of real estate in Portugal made for consideration. The buyer owes it, and it is charged on whichever is higher: the value in the contract or the property's taxable value (VPT). There is no single rate — the table is banded, and it changes with what the property will be used for and where it is.
In practice
On a house purchase, IMT is the largest cost on top of the price. It is assessed before the deed and must be paid for the deed to go ahead. For a buyer's own permanent home the first band is free up to 106 346 €, and a first purchase by someone aged up to 35 uses a separate, more favourable table.
Payment is due on the day of assessment or within the 30 days that follow; after that the assessment lapses and a new one has to be requested. The flatin.pt IMT calculator uses the tables in force and shows, in the same result, the stamp duty owed on the purchase.