Due diligence when buying property in Spain — what gets checked and why it matters

Why due diligence exists

Buying property in Spain as a foreigner is not inherently risky. But buying without proper legal checks is. Due diligence is the process your lawyer carries out between the moment you agree on a property and the moment you sign anything binding. Its purpose is simple: confirm that the property is legally what the seller says it is, that it is free of debts and charges, and that you are safe to proceed.

This is not a formality. It is the single most important phase of the entire purchase. Properties in Spain can carry debts that transfer to the new owner. They can have planning irregularities that only surface after completion. They can have boundaries that do not match what is registered. Due diligence catches these problems before they become yours.

If your lawyer is not carrying out the checks described in this article, they are not doing their job.

The nota simple

The nota simple is the most important document in any Spanish property transaction. It is an extract from the Land Registry — the Registro de la Propiedad — and it tells you three critical things about the property: who owns it, what is registered, and what charges or debts are attached to it.

What the nota simple contains

Ownership. The full legal names of the current registered owner or owners. If the person selling the property is not the person named on the nota simple, that is a problem that needs resolving before anything else happens.

Property description. The registered boundaries, size, location and referencia catastral of the property. This is the legal definition of what you are buying — not what the listing says, not what the agency describes, but what the Land Registry holds on record.

Charges and encumbrances. Any mortgages, liens, embargoes or legal claims registered against the property. A property with an outstanding mortgage is not unusual — it simply means the mortgage must be cancelled at or before completion. But a property with an embargo or a legal dispute attached to it is a different matter entirely.

What to watch for

Your lawyer should request an up-to-date nota simple — not one from six months ago. The Land Registry is a live record. A charge can be registered between the time a nota simple is issued and the time you sign. Your lawyer should request a fresh copy close to the signing date and, ideally, check again on the day of completion.

If the property description on the nota simple does not match what you are physically looking at — different size, different boundaries, additional structures not mentioned — that is a red flag. It does not necessarily mean fraud, but it means something has not been declared or registered correctly, and your lawyer needs to investigate before you proceed.

The referencia catastral

The referencia catastral is the unique identifier assigned to every property in Spain by the Catastro — the national land and property register managed by the tax authorities. It is separate from the Land Registry. Think of the Land Registry as the legal ownership record and the Catastro as the physical and fiscal record.

Why it matters

The referencia catastral confirms the physical reality of the property — its location, boundaries, built area and plot size according to official records. Your lawyer cross-references this against the nota simple to check that the legal record and the fiscal record match. Discrepancies between the two are more common than you might expect, particularly with older properties, rural fincas or properties that have had extensions or modifications over the years.

Common discrepancies

A property may have a registered built area of 120m² on the Catastro but 150m² on the nota simple — or the other way around. This usually means a modification was declared to one register but not the other. It does not always indicate a serious problem, but it needs resolving. If you buy a property with undeclared built area, you inherit the problem — and potentially the fine.

On the Costa Blanca, this is particularly common with properties that had extensions, covered terraces or pool houses added during the construction boom of the early 2000s. Many of these were built with local licences but never formally declared to the Catastro or the Land Registry. Your lawyer checks for this specifically.

Urban planning compliance

Your lawyer checks whether the property complies with the local urban planning regulations — the Plan General de Ordenación Urbana (PGOU) of the municipality where the property is located. This confirms that the property was built legally, that any modifications were licensed, and that no part of the property sits on protected or non-buildable land.

What can go wrong

In some parts of the Costa Blanca, properties were built on land that was later reclassified. A villa that was perfectly legal when constructed may now sit on land designated as protected, green zone or public domain. This is rare in established urban areas like Moraira or Jávea, but it is a real risk with rural properties, inland fincas and properties near the coastline.

Your lawyer also checks for any open planning files (expedientes urbanísticos) against the property. An open file means the local town hall has identified a potential infraction — an unlicensed extension, a swimming pool built without permission, a boundary encroachment — and has not yet resolved it. Buying a property with an open planning file means you take on that unresolved issue.

Outstanding debts and charges

In Spain, certain debts attach to the property, not to the person. This means that if you buy a property with outstanding debts, those debts become yours.

What your lawyer checks

Community fees. If the property is part of a community of owners — which includes most urbanisations, apartment buildings and some townhouse developments — your lawyer requests a certificate from the community administrator confirming that all fees are paid up to date. Unpaid community fees transfer to the buyer.

IBI (Impuesto sobre Bienes Inmuebles). This is the annual property tax paid to the local town hall. Your lawyer confirms that all IBI payments are current. Unpaid IBI is a debt that follows the property.

Utility bills. Outstanding water, electricity or gas bills can in some cases result in supply being cut or a lien being placed. Your lawyer checks that utilities are current and that the contracts are in the seller's name.

Mortgage. If the seller has an outstanding mortgage on the property, it must be cancelled at or before completion. This is routine — the seller's bank issues a cancellation certificate and the mortgage is lifted from the Land Registry. Your lawyer ensures this happens before the purchase is registered in your name.

The licencia de segunda ocupación

This is specific to the Valencian Community — which includes the entire Costa Blanca — and it catches many foreign buyers off guard.

What it is

The licencia de segunda ocupación (sometimes called the cédula de habitabilidad in other regions) is a certificate issued by the local town hall confirming that a resale property meets current habitability standards. It covers structural condition, sanitation, electrical installation, water supply and basic safety requirements.

Why it matters

In the Valencian Community, you need this certificate to transfer utility contracts into your name after purchase. Without it, you may not be able to set up water or electricity in your own name — which means you cannot legally occupy the property as intended.

The certificate is the seller's responsibility to obtain before completion. However, not all sellers have it ready, and obtaining it can take several weeks depending on the municipality. If the property requires updates to meet current standards — a new electrical certificate, for example — the process takes longer.

What your lawyer should do

Your lawyer should confirm early in the process whether the seller has a valid, current licencia de segunda ocupación. If they do not, this becomes a negotiating point — either the seller obtains it before completion, or the purchase price reflects the cost and delay of the buyer obtaining it afterwards. This should never be a surprise that surfaces at the notary.

When due diligence typically happens

Due diligence runs in parallel with the reservation and contrato de arras phase. In a typical Costa Blanca transaction, the timeline looks like this:

Week 1. You agree on a price and pay a reservation deposit to take the property off the market. Your lawyer begins requesting documentation — nota simple, referencia catastral, community fee certificate, IBI receipts, utility records, licencia de segunda ocupación.

Weeks 2–4. Your lawyer reviews everything, cross-references the records, checks for discrepancies and flags any issues. If problems are found, they are raised with the seller's side before the contrato de arras is signed.

Week 3–5. The contrato de arras is signed once your lawyer confirms that the property is legally clean — or that any identified issues have been resolved or accounted for in the contract terms.

Completion. Your lawyer does a final check on the nota simple close to the signing date to confirm nothing has changed since the initial review.

The entire due diligence process typically takes 3 to 5 weeks. Rushing it is not advisable. Skipping it is reckless.

What happens if due diligence finds a problem

Not every issue uncovered during due diligence means the purchase falls through. Most problems have solutions — they just need to be identified before you commit.

Minor discrepancies between the Catastro and the Land Registry can often be corrected with a simple administrative process. Your lawyer handles this.

Outstanding debts are typically settled by the seller at or before completion. Your lawyer ensures the contract includes a clause requiring this.

Missing licencia de segunda ocupación can be obtained by the seller before completion, or the contract can be structured to account for the buyer obtaining it afterwards at the seller's cost.

Serious issues — such as an open planning file, undeclared construction, disputed ownership or a property built on protected land — are grounds to walk away. If your lawyer discovers something that cannot be resolved, and you have not yet signed the contrato de arras, you recover your reservation deposit and move on. This is exactly why due diligence happens before you sign, not after.

The honest summary

Due diligence is not glamorous. It is not the part of buying a property that anyone gets excited about. But it is the part that protects you from buying a problem instead of a property.

A competent, independent lawyer — one who works for you, not for the agency and not for the seller — is the only person who can carry this out properly. Do not rely on the agency to handle legal checks. Do not assume that because a property is listed on a portal, it has been legally vetted. And do not skip this process because the property looks perfect and the seller seems honest.

The nota simple, the referencia catastral, the planning compliance, the debts, the licencia de segunda ocupación — these are not bureaucratic hurdles. They are the checks that ensure what you are buying is actually what you think it is.

If you are looking for independent legal professionals on the Costa Blanca, the professionals directory lists verified lawyers who work with foreign buyers in this region.

Frequently asked questions about due diligence in Spain

What is a nota simple and why do I need one?

The nota simple is an extract from the Spanish Land Registry showing ownership, property description and any charges or debts registered against the property. It is the first document your lawyer requests and the foundation of the entire due diligence process.

How long does due diligence take when buying in Spain?

Typically 3 to 5 weeks. Your lawyer requests and reviews all documentation during this period. Rushing the process increases the risk of missing something that could cost you significantly more than the time saved.

What is the licencia de segunda ocupación?

A certificate issued by the local town hall in the Valencian Community confirming that a resale property meets habitability standards. You need it to transfer utility contracts into your name. It is the seller's responsibility to provide, but your lawyer should confirm its status early in the process.

What debts can transfer to me when I buy a property in Spain?

Unpaid community fees, outstanding IBI (property tax), and in some cases utility debts can attach to the property rather than the person. Your lawyer checks all of these before you sign anything binding.

Can I do my own due diligence without a lawyer?

You can request a nota simple yourself from the Land Registry. But interpreting it, cross-referencing it against the Catastro, checking planning compliance, verifying debts and confirming the licencia de segunda ocupación requires legal expertise and local knowledge. This is not a process to handle alone.