IMI (Imposto Municipal sobre Imóveis) is Portugal's annual municipal property tax, charged every year to whoever owns a property on 31 December of the prior year, and calculated on the property's VPT (valor patrimonial tributário, the tax-assessed value, not the market price). AIMI (Adicional ao IMI) is a separate, additional annual tax that applies only to individuals and entities whose combined VPT of residential and building-land property exceeds a deduction threshold. This document covers only these two recurring annual taxes — not IMT, the one-time property transfer tax charged at purchase.
Every property owner in Portugal — resident or non-resident — owes IMI every year for as long as they own the property, so it is a recurring cost to budget into cost-of-living and rental-yield calculations. AIMI mainly affects owners of higher-value property portfolios or single high-VPT homes, which is relevant to newcomers buying premium property. Missing payment deadlines or failing to claim an available exemption (e.g., for a lower-value primary residence) can mean overpaying or facing enforcement action.
Key Facts
IMI applies to the VPT of urban and rural ("rústico") properties as registered with the Autoridade Tributária.
IMI rates are set annually by each municipality (câmara municipal) within legal bands:
Urban properties (prédios urbanos): 0.3% to 0.45% of VPT (up to 0.5% in specific exceptional cases set by law).
Rural/rustic properties (prédios rústicos): up to 0.8% of VPT.
The applicable rate depends on the municipality where the property is located — coastal cities and Lisbon/Porto-area municipalities often set rates near the upper end of the urban band, while some inland municipalities set lower rates; check the specific concelho's published rate each year.
IMI is owed by whoever is registered as owner, usufructuary, or "superficiário" of the property as of 31 December of the year to which the tax relates, even if the property is sold shortly after.
Payment is split into installments based on the total amount due for the year: a single payment in May if the total is up to €100; two installments (May and November) if between €100 and €500; three installments (May, August, and November) if over €500.
AIMI applies to the sum of VPTs of urban residential property and building land ("terrenos para construção") held by an individual, on 1 January of the relevant year.
For individuals, a deduction of €600,000 is applied to the total taxable VPT before AIMI is calculated; this deduction doubles to €1,200,000 for married couples or de facto partners who opt for joint AIMI taxation.
AIMI marginal rates for individuals: 0.7% on the taxable value up to €1,000,000 (i.e., after the deduction, on the band up to €1,000,000); 1% on the portion between €1,000,000 and €2,000,000; 1.5% on the portion above €2,000,000. Undivided estates (heranças indivisas) are taxed at a flat 0.7% rate.
AIMI is assessed by the Autoridade Tributária each June and paid in a single installment in September.
Married couples/de facto partners can elect joint AIMI taxation (to access the doubled €1,200,000 deduction) between 1 April and 31 May of the relevant year.
A temporary IMI exemption (up to 3 years, extendable by up to 2 more years via municipal assembly decision) is available under Article 46 of the Estatuto dos Benefícios Fiscais for a property used as the owner's primary permanent residence, subject to conditions: the owner/household's gross annual income does not exceed €153,300, and the property's VPT does not exceed €125,000. For onerous acquisitions, the exemption is applied automatically by the Autoridade Tributária based on available information; otherwise it must be requested within 60 days of the six-month deadline to establish the property as the tax residence.
Steps
Confirm the property's VPT — Check the VPT shown on the property's caderneta predial (available via the Portal das Finanças) — this figure, not the purchase price or market value, is the base for both IMI and AIMI.
Check the municipality's current IMI rate — Each câmara municipal publishes its applicable annual IMI rate within the legal bands; confirm the current rate for the specific concelho, since it changes the amount owed even for an identical VPT.
Check eligibility for the primary-residence IMI exemption — If the property will be your permanent residence, verify whether your household income and the property's VPT fall under the Article 46 EBF thresholds; if buying (onerous title), the exemption is normally applied automatically, but confirm on the Portal das Finanças (Cidadãos > Imóveis > IMI > Pedidos > Pedido de Isenção) and follow up if it is not reflected.
Monitor AIMI exposure — If you own (or plan to own) residential property and/or building land with a combined VPT above €600,000 (or €1,200,000 jointly with a spouse/partner electing joint taxation), budget for AIMI, assessed in June and payable in September.
Pay IMI on schedule — Pay via the payment reference issued by the Autoridade Tributária (Portal das Finanças, home banking Multibanco/MB Way, or at a CTT/Finanças counter) according to the May/August/November installment schedule that applies to your total amount due.
Costs
IMI rate, urban property: 0.3% – 0.45% of VPT (up to 0.5% in specific cases), set by each municipality
IMI rate, rural/rustic property: up to 0.8% of VPT
AIMI rate (individuals), taxable value up to €1,000,000: 0.7%
AIMI deduction before calculation, individuals: €600,000 (doubled to €1,200,000 for couples electing joint taxation)
Timelines
IMI payment (total due ≤ €100): single installment, May
IMI payment (total due €100–€500): two installments, May and November
IMI payment (total due > €500): three installments, May, August, and November
AIMI assessment: June (by the Autoridade Tributária)
AIMI payment: single installment, September
AIMI joint-taxation election window (married/de facto couples): 1 April – 31 May
Primary-residence IMI exemption request (if not automatic): within 60 days after the 6-month deadline to establish tax residence at the property
Required Documents
Caderneta predial (property tax record, shows the VPT)
NIF (tax number)
Proof of primary-residence status (domicílio fiscal) if applying for the Article 46 EBF exemption
Proof of household income if applying for the primary-residence exemption
Common Mistakes
Assuming IMI is based on the purchase/market price rather than the VPT, which can differ substantially.
Not checking whether the seller or buyer owes IMI for the year of a sale — liability follows whoever owned the property on 31 December of the prior year, regardless of a later sale.
Overlooking AIMI exposure when buying a high-VPT residence or land, or when a couple should elect joint taxation to access the higher €1,200,000 deduction.
Missing the AIMI joint-taxation election window (1 April–31 May), which cannot generally be applied retroactively.
Not applying for the Article 46 EBF primary-residence exemption when eligible, or missing the 60-day window when it isn't applied automatically.