The instalment falling due on 30 November 2026 isn’t a bill for 2026. Portugal settles IMI in February and April of the year after the one the tax refers to, so what is being collected this month is the 2025 charge, raised on whoever appeared in the municipal property register on 31 December 2025. The tax code states both halves plainly: the taxpayer is the person listed in the matriz on 31 December of the tax year, and the settlement itself follows the next spring.
That one year gap answers the question every foreign buyer asks at the signing table, and it’s the reason the deed needs a clause about the year of the sale. What follows is the instalment ladder, the rate that changes at a concelho border, the multiplied bill on an empty building, and the single figure in the caderneta predial that decides all of it.
Who Owes the IMI on the Year You Buy the House
Article 113 works in two steps. It settles the tax, municipality by municipality, on the taxable value of the building and on the taxpayers who are in the register on 31 December of the year it refers to. That settlement is then made in February and April of the following year, which is why last year’s bill is only reaching its final instalment now.
Follow a purchase through it. Complete on 20 December 2026 and the register at the end of that month carries your name, so the whole of 2026 becomes your bill when it’s settled in spring 2027, including eleven months when the seller had the keys. Complete on 20 January 2026 instead, and the 2025 tax you’re paying this month was already the seller’s, settled before your name appeared in the file. Both sides usually agree to split the year, and that split is a private arrangement: the tax office reads the register, not the clause, so the clause belongs in the escritura rather than in an exchange of emails. Whoever is named in the register pays first and argues afterwards.
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The Instalment Ladder and What a Missed One Costs
Article 120 fixes the ladder by the size of the bill, and the bands haven’t moved since Lei 71/2018. Up to €100 you pay once, in May. From €100 to €500 it comes in two parts, May and November. Above €500 there are three dates: May, August and November. What’s being closed out now is the 2025 bill, with a final deadline of 30 November 2026, and its reference sits in the Portal das Finanças under consultar notas de cobrança or pagamentos a decorrer.
Miss one instalment and the rest fall due at once. A single late instalment triggers the fourth paragraph of the same article, which makes the remaining ones immediately payable, and under Article 44 of the general tax law interest runs on the unpaid amount until the day it’s settled. Two smaller rules are worth carrying into a budget. Nothing under €10 is ever billed at all, and the married couple treatment, which applies the bands to a couple’s total rather than to each half of a shared title, covers only the home where they live permanently and hold their fiscal domicile. A holiday home gets no such help. Keep the figure beside the other property taxes a Portuguese owner meets, because the two bills arrive months apart and each one looks like the only one.
Why an Empty Ruin Can Be Taxed Twenty Times Over
Article 112-B is the clause that ambushes buyers of cheap ruins, and it entered the property tax code with the 2023 housing law, Lei 56/2023. Three things have to line up before it bites:
- an urban building or an autonomous fraction that has stood empty for more than a year, or is a ruin, or is building land with housing aptitude inside urban soil;
- a location inside an area formally declared an urban pressure zone, which is a legal designation rather than a description;
- a rate to multiply, which is the ordinary municipal rate the local council has set for the year.
Where all three meet, that rate is multiplied by ten. It then climbs by another 20% in each following year, up to a ceiling of twenty times the base rate.
Municipalities can lift that ceiling too: by 50% where the home isn’t rented out or used as a permanent residence during the year, and by 100% where the owner is a company or a similar entity. Run a modest example, which is my arithmetic rather than the authority’s. A taxable value of €120,000 at 0.35% gives €420 a year, the sort of figure a village house in the Algarve carries. In a pressure zone the first year becomes €4,200, the second €5,040 and the ceiling €8,400. A company holding an empty building with the doubled ceiling reaches €16,800.
What to Read in the Caderneta Before You Sign
All of it is charged on the valor patrimonial tributário, the taxable value printed in the caderneta predial, not on the price you agreed. The tax authority’s own page gives the bands: urban buildings from 0.3% to 0.45%, up to 0.5% in exceptional cases, and rustic land up to 0.8%. Each municipality sets its rate every year inside those limits, so the same house carries a different bill on either side of a concelho border. House prices move with the market and the taxable value doesn’t, which makes Portugal property a poor thing to budget from the asking price alone.
| Charge | Base | Rate | When it’s paid |
|---|---|---|---|
| IMI, single payment | tax up to €100 | 0.3% to 0.45% urban, up to 0.8% rustic | May |
| IMI, two instalments | tax from €100 to €500 | same bands | May and November |
| IMI, three instalments | tax above €500 | same bands | May, August and November |
| Vacant building in a pressure zone | taxable value | ×10, then 20% a year, capped at 20× | with the ordinary IMI |
| AIMI | urban housing value above €600,000 | 0.7% to 1.5% | September |
September’s line is a different tax on its own clock. AIMI is charged to whoever holds the property on 1 January of the tax year, worked out by the authority during June and notified for a single payment in September. It applies to the total urban housing value above a €600,000 deduction, which doubles to €1,200,000 for couples who elect joint taxation, and the rates run at 0.7% to €1,000,000, 1% on the excess to €2,000,000 and 1.5% above that. An owner who clears the threshold gets two bills a year, and the November instalment is IMI only.
What an Agent Should Confirm Before Completion
Six checks, in ascending order of what they cost to get wrong. Each one corresponds to a place where a buyer’s annual budget has already gone off the rails.
- Ask for the caderneta predial and read the taxable value, not the asking price. That figure decides the annual bill, and it rarely moves in line with the market.
- Get the municipal rate for the year from the municipality or the tax portal. Two neighbouring concelhos can sit at opposite ends of the 0.3% to 0.45% range.
- Ask for last year’s nota de cobrança. It shows what the house actually costs to hold and whether it is being billed at the ordinary rate.
- Count the instalments: above €500 of tax there are three dates, not one, and the last of them lands in late November.
- If the property is a ruin or has stood empty, establish whether it sits in an urban pressure zone before assuming a modest bill. That answer is worth a factor of ten.
- Put the year of the sale in the deed, naming who pays the IMI of the year in which the keys change hands. Without it, the register decides for you.
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What the Register Rule Means for a Foreign Buyer
This rule surprises people, and it’s also the cheapest to fix. Whoever is in the matriz on 31 December carries the year, so the deed is the only place to write down who really pays for it. Read the caderneta before you fall for the view, and remember that the number under the rate is one the tax office maintains, not the one you negotiated in the summer.
None of this makes IMI a reason to walk away. A taxable value of €150,000 costs €525 a year at 0.35%, which is small next to what the notary and the transfer tax take on the day of the deed. It’s the compounding versions that bite: an empty building in a pressure zone, a ruin left standing for years, a company holding the title. Budget the annual charge the way you’d budget insurance, and the November date stops being a surprise.
Questions Buyers Ask About Portuguese IMI
Do I pay IMI for the year I buy in Portugal?
Only if you’re in the property register on 31 December of that year. Whoever appears there at the end of the year gets the bill, whatever the deed says about splitting the months, and it arrives the following spring.
When is the last IMI instalment due in 2026?
30 November 2026 for anyone billed more than €100. Both the two instalment band, from €100 to €500, and the three instalment band above €500 end in November. Below €100 the whole amount was paid in May.
Is IMI charged on the price I paid?
No. It’s charged on the valor patrimonial tributário in the caderneta predial, a value the tax office keeps and which usually predates your purchase. Multiply that figure by the municipal rate to see the real annual cost of a house.
What happens if I miss an instalment?
The remaining instalments fall due immediately, so a missed August payment doesn’t wait politely for November. Interest runs on the unpaid tax until it’s settled, and the amount becomes a tax debt the authority can pursue through its own collection process.
Does a company pay more IMI on an empty building?
It can. Inside an urban pressure zone the rate is multiplied by ten and rises 20% a year, and the twenty times ceiling doubles where the owner is a company or a comparable entity. Foreign buyers who hold a Portuguese ruin through a company are the usual case.
