IMT and Stamp Duty when buying a house: how the brackets work

Key points

This guide explains how IMT and Stamp Duty work when buying a house, without stating fixed figures that change every year. For an exact calculation for your case, always use the Tax Authority's official simulator.

1. What value the taxes are based on

IMT and Stamp Duty apply to the higher of the price stated in the contract and the property's tax value, shown in the tax property record. This means that if the tax value is higher than the agreed price, the taxes are calculated on that higher value.

Always confirm the property's current tax value before budgeting your purchase, as it may have been revised since your last tax property record was issued.

• Compare the purchase price and the tax value.
• Always use the higher of the two figures.
• Confirm the current tax value before budgeting.

2. How IMT brackets work

Article 17 of the IMT Code organises the tax into progressive marginal brackets: when the taxable value exceeds a bracket's limit, the portion within the bracket is taxed at that bracket's rate and the excess at the next bracket's rate, with a deductible amount to simplify the total calculation.

For a primary residence, rates range from 0% up to a maximum of 7.5% for higher values; for other housing, the first bracket starts at 1% and also rises to 7.5%. Rural and other urban properties have their own rates. The exact euro limits of each bracket change every year under budget legislation — always check the current figures on the Finance Portal.

• Understand that IMT uses marginal bracket rates, not a single flat rate.
• Confirm whether the property is a primary residence or another use.
• Check the current bracket figures on the Finance Portal.

3. Stamp Duty: a fixed rate on the purchase and on the loan

Stamp Duty applies to the purchase at a fixed rate of 0.8% on the same base as IMT, regardless of the bracket. If you use mortgage credit, the financed amount is also subject to Stamp Duty, at its own rate for loans.

Unlike IMT, Stamp Duty has no progressive brackets — the rate applies uniformly to the taxable value, which makes this specific tax easier to estimate in advance.

• Confirm the fixed 0.8% Stamp Duty rate on the purchase.
• Factor in the additional Stamp Duty on the financed amount.
• Do not confuse Stamp Duty's flat mechanism with IMT's brackets.

4. IMT Jovem and other exemptions

Buyers up to age 35 may qualify for an IMT exemption when buying a primary residence, subject to conditions such as not having owned housing in recent years and the property value not exceeding a limit updated annually.

Other exemptions and tax benefits apply in specific situations. Always confirm with the Tax Authority that you meet the conditions before assuming an exemption applies to your case.

• Check the age and prior-ownership requirements for IMT Jovem.
• Confirm the current property value limit.
• Do not assume an exemption without confirming it with the Tax Authority.

5. Modelo 1 declaration and simulating costs before buying

IMT and Stamp Duty are settled through a Modelo 1 declaration, submitted via the Finance Portal or in person, with proof of payment required before the deed or Casa Pronta appointment.

Before committing, use the Tax Authority's official simulator to estimate these taxes based on the price and characteristics of the property, and include that figure in your total purchase budget.

• Submit the Modelo 1 declaration before completion.
• Keep proof of payment for the completion appointment.
• Use the official simulator to estimate the total cost before buying.