Most expensive mistakes in Portuguese property are not bad prices. They are liabilities the buyer did not see: a mortgage still registered, a condominium bill, a tenant with a right to buy first, a missing use title. Each can be found with a document that costs between nothing and €15.

This due diligence checklist is written for investors, so it is ordered by what destroys a return, and it is timed for the moment that matters: before you sign the promissory contract and pay the deposit. It also covers the deed rule that changed on 1 October 2026.

Key takeaways: Run every check before paying the sinal, because under article 442 of the Civil Code a defaulting buyer loses it. The land registry certificate costs €15 online and lasts six months. Since 1 October 2026 the deed must record whether an urban use title exists (DL 108/2026). Never waive the condominium debt declaration, and ask for proof that recent IMI is paid.

  1. Land registry certificate (certidão permanente)
  2. Tax record (caderneta predial urbana)
  3. Urban use title
  4. Energy certificate
  5. Condominium debt declaration
  6. Preference rights (tenant and public bodies)
  7. Existing lease
  8. AL registration, for short lets
  9. Proof that recent IMI is paid

Why must the checks happen before the deposit?

Because the deposit is the point of no cheap return. Under article 442 of the Portuguese Civil Code, if the buyer fails to complete, the seller keeps the sinal. If the seller fails, the buyer can demand double what was paid, or ask a court to enforce the sale. A problem you discover after signing becomes a negotiation from a weak position.

The promissory contract (contrato-promessa) for a building has its own formality. Article 410(3) of the Civil Code requires signatures recognised in person and certification that a use or construction licence exists. If a seller cannot support that certification, you have learned something important before any money moves.

In practice, investors should order the documents as soon as the price is agreed in principle, and make the promissory contract conditional on anything still outstanding. Combine this with the valuation check in our guide to bank appraisal versus asking price if you are borrowing.

What do the land registry certificate and the caderneta show?

Who owns the property, what is registered against it, and how the tax authority values it. These two documents are the foundation, and they should match each other and the listing.

The certidão permanente do registo predial, from the Registos e Notariado (IRN), shows every registration currently in force on the property, plus pending requests. That is where a bank mortgage, a seizure (penhora) or another encumbrance appears. Anyone can order it on Predial Online with a name and email. It costs €15 online, €20 at a registry office, and stays valid for six months.

The caderneta predial urbana comes from the tax authority (AT). It identifies the property, its features, its owners and its taxable value (VPT), and it is valid for 12 months. Only the owner can download it on Portal das Finanças, so ask the seller for it. The VPT drives your annual IMI, which you can estimate with the IMI calculator; our IMI guide explains why a purchase can trigger a reassessment.

What to compare: the owner on the certificate must be the person signing, the area should match the listing, and any mortgage must be cancelled at or before the deed. A seller with a registered mortgage is normal. A seizure is not.

What changed for the licença de utilização on 1 October 2026?

The deed must now say whether the property has an urban use title. Decreto-Lei 10/2024 removed, from 1 January 2024, the obligation to present the use permit (autorização de utilização) and the technical housing file (ficha técnica) at the deed. Many buyers read that as "the licence no longer matters". It never meant that, and the 2026 reform makes the point explicit.

Decreto-Lei 108/2026, in force since 1 October 2026, rewrote the urban planning regime (RJUE). The use title now passes automatically with the property. And when a built property or flat is sold, the notary, lawyer or solicitor must record one of three things in the deed, under penalty of the sale being annullable:

  • that the urban title exists and was presented;
  • that the seller declares having it, without presenting it; or
  • that the seller declares having no urban title.

Our reading for investors: the third line is now written into your deed for every future buyer and lender to see. A flat without a use title can still be sold, but expect it to be harder to finance and to resell, and price it that way. Ask for the title, or the municipal reference, before the promissory contract, and check that its use (housing) matches what you plan to do.

In short: Since 1 October 2026, under Decreto-Lei 108/2026, every deed for a built property in Portugal must record whether the urban use title was presented, whether the seller says they hold it, or whether the seller declares there is none. The title transfers automatically with the property. Investors should obtain it before paying a deposit.

The energy certificate is a legal duty, not paperwork

It carries fines and a rental consequence. Under Decreto-Lei 101-D/2020 a valid energy certificate is required when a property is sold or let, and the owner must give the buyer a copy before the promissory contract is signed. The energy class must also appear in every advertisement.

Fines for the owner run from €250 to €3,740 for individuals and €2,500 to €44,890 for companies. A certificate is normally valid for ten years, according to ADENE's SCE portal, which also lets you look up any certificate before a visit.

For an investor the class matters more than the paper. A poor rating changes your renovation budget and, over time, what you can let. Our analysis of energy certificates and ROI covers that in detail.

How do you avoid inheriting condominium debts?

Insist on the administrator's declaration. Article 1424-A of the Civil Code, added by Lei 8/2022, makes the seller request a written statement from the building administrator of all charges and any debts on the flat. The administrator must issue it within 10 days of the request.

The trap is a single sentence. The buyer may declare at the deed that they waive the statement, and by doing so takes on the seller's condominium debts. Charges that fall due after the sale belong to the new owner in any case. Our advice is blunt: never waive it, and read it together with the minutes of the last two building meetings, where approved works and special levies show up first.

Tenants, public bodies and AL: other rights over the property

Tenants, public bodies and, for short lets, the condominium and the municipality can each change what you are actually buying.

  • A sitting tenant may buy first. Under article 1091 of the Civil Code, a tenant of more than two years has a right of first refusal on a sale and has 30 days from receiving the offer to answer.
  • Public bodies may too. In classified areas, protected zones and urban rehabilitation areas (ARU), the State or municipality can have a legal preference right. Sellers announce the sale on the Casa Pronta platform for €15; public bodies have 10 working days to respond, and if they do not, the right lapses.
  • The lease comes with the flat. Under article 1057 of the Civil Code the buyer steps into the landlord's rights and obligations. Read the contract, the rent, the last update and the deposit held before pricing the deal. Our rent update guide explains how far a sitting tenant's rent can move.
  • An AL licence may not travel well. The registration on the Balcão Único is the only valid title to operate a short let, and since Decreto-Lei 76/2024 municipalities can limit the transfer of new registration numbers. The condominium can also ask for an AL unit to be closed, by a reasoned resolution backed by more than half of the building's permilage, on grounds of repeated and proven disturbance. Check the municipal rules and the minutes before paying for "an AL business".

Can the seller's unpaid taxes follow the property?

Recent IMI can. IMI is owed by whoever owns the property on 31 December of the year in question (article 8 of the IMI code), and article 122 of the IMI code gives it the special guarantees of the Civil Code. Article 744 gives property-tax credits for the current year and the two before a privilege over the property itself, and article 751 makes that privilege enforceable against later buyers, ahead of a mortgage.

So ask the seller for proof that IMI is paid for the last three years, and for the AT's statement of no tax debts if you can get it. Then check planning: the municipal master plan (PDM) and any other territorial plans can be consulted online through the DGT's SNIT service. If you plan to extend, change use or split a property, read the plan before you offer, not after.

What skipping due diligence costs an investor

Usually far more than the check itself. Take an illustrative deal, with our own assumptions: a €200,000 flat let at €900 a month, a €20,000 deposit (10%), a building with €3,000 of unpaid condominium charges, and €540 of unpaid IMI from previous years (0.3% on a €90,000 VPT, two years).

ItemCost of checkingCost if missed
Land registry certificate€15Unknown seizure or mortgage blocks the deed; deposit at risk (€20,000)
Condominium declarationFree to the buyer€3,000 of the seller's debts if waived
IMI proofFree€540 enforceable against the property
Preference announcement€15 (paid by the seller)A public body or tenant buys instead; months lost
Urban titleFree to ask"No title" on the deed; harder financing and resale

The two liabilities alone, €3,540, equal almost four months of rent and about 1.8% of the price. On a 5.4% gross yield, that is a third of the first year's gross income gone before the tenant moves in. Add them to your acquisition costs in the deal score calculator and the IMT calculator, and see what the deal looks like with them included.

Our verdict: the checklist costs the buyer about €15 and a week. Buyers who skip it are not saving money; they are betting the deposit on the seller's paperwork. For auctions, where the rules are different, see our guide to bank and tax-authority auctions, and if you buy as a non-resident, factor in the flat 7.5% IMT before the deposit too.

This article is general information, not legal, tax or financial advice. A Portuguese lawyer or solicitor should review the documents and the contracts for any specific purchase.

Sources

Frequently asked questions

What documents should I check before buying property in Portugal?

At minimum: the certidão permanente from the land registry (€15 online, valid 6 months), the caderneta predial from the tax authority, the urban use title, the energy certificate, the condominium debt declaration, any existing lease, and proof that recent IMI has been paid.

Do I still need a licença de utilização to buy a property in Portugal?

Since 2024 it has not had to be shown at the deed. But from 1 October 2026, under Decreto-Lei 108/2026, the deed must record whether the title was presented, whether the seller declares having it, or whether the seller declares having none, under penalty of annulability.

Can I inherit the seller's condominium debts?

Yes, if you waive the declaration. Article 1424-A of the Civil Code requires the seller to obtain a written statement of charges and debts from the building administrator, issued within 10 days. A buyer who declares at the deed that they waive it takes on the debts.

What happens to my deposit if the seller pulls out?

Under article 442 of the Civil Code, if the seller defaults you can demand double the deposit (sinal), or ask a court to enforce the sale. If you default, the seller keeps the deposit. That is why every check should happen before you pay it.