Property due diligence in Spain: the checks before you sign

Property due diligence in Spain, check by check: registry, Catastro, licences, planning, debts that follow the house, coastal and rustic land, and extensions.

Last checked 17 October 2026

What you will learn

What the nota simple and the Catastro tell you, and what they miss
Which debts stay with the house when you buy it
Why an unlicensed extension is your problem after the sale

Property due diligence in Spain means checking, before you sign anything binding, that the house exists legally as you see it, belongs to the seller, carries no hidden debts and can be used the way you plan. Most of it is paperwork your lawyer obtains from the land registry, the Catastro and the town hall. Done before the private contract, it costs little. Done afterwards, a bad surprise can cost you the deposit. The checks are one stage of buying property in Spain step by step; here they are in the order a lawyer usually runs them.

It starts at the registry

The nota simple. The first document is the nota simple from the land registry. It identifies the property and its registered owners and lists what limits it: mortgages, embargoes and other charges. The registrars' online service can add an English translation if you ask for one. The extract also shows whether the registry description is coordinated with the Catastro.

Why the registry matters. Spanish law protects a person who buys in good faith from the registered owner and then registers, while a title that is not registered does not affect third parties. So the seller must be the registered owner, every registered owner must sign, and if the house is a family home the spouse's consent may be needed. A nota simple shows the position on the day it is issued, so your lawyer will look again shortly before the deed.

The Catastro and the real house

The Catastro. The Catastro is the tax map of Spain. Anyone can look up a property's non-protected data and its plan online, without logging in. Compare three things: the built area in the Catastro, the area in the registry, and what stands on the plot. A pool, a covered terrace or a guest flat that you can see on site but that appears in neither record is a question for the town hall, not a detail. The cadastral reference also appears on the IBI receipt, which the notary uses to identify the property.

Licences, planning and extensions

The occupation licence. In the Comunitat Valenciana a home needs an occupation licence, which today is usually a declaración responsable for first or later occupation filed with the town hall. Under the Valencian building law, once ten years have passed since the first licence, it must be renewed when the property is sold again or when a new water, gas or electricity contract is signed. Ask the seller for the licence and its date.

The planning position. Ask the town hall in writing for the zoning and classification of the plot: urban, developable or non-developable (rustic). Under the Valencian planning law (TRLOTUP), the town hall must answer such a request within one month. For a plot that can be built on, it can also issue a cédula de garantía urbanística, valid for up to one year.

Building work without a licence. In the Valencian region the town hall can order the restoration of planning legality for works done without a licence for fifteen years after they were finished. On non-developable land, green zones, roads and public land there is no time limit at all. Passing fifteen years does not make the work legal either: the law says that such parts cannot be reformed, extended or consolidated while the breach lasts. An unlicensed extension is therefore a problem you buy with the house. Ask your lawyer and an architect to compare the licences with what is built.

Debts that follow the house

IBI. The annual property tax stays attached to the property: if the seller has left it unpaid, the house answers for it after the sale. The notary requests information on IBI debts and warns the parties in the deed. Ask for the last receipt.

Community fees. Where the house belongs to a community of owners, as in many urbanisations, the horizontal property law makes the buyer answer, with the property, for unpaid fees of the current year and the three previous calendar years. At the deed the seller must declare that the fees are paid and bring a certificate from the community, which its secretary must issue within seven days. Without it the notary cannot sign, unless the buyer expressly waives it. There is rarely a good reason to waive it.

Mortgages and embargoes. Any charge shown in the nota simple has to be cancelled at or before the deed, usually by paying the seller's bank out of the price at the signing. Your lawyer arranges the cancellation and makes sure it reaches the registry.

Coast, rustic land and natural risks

The coast. Near the sea, the coastal law applies. Under the Ley de Costas, land within 100 metres inland of the shore carries a protection easement, reduced to 20 metres where the land was already classified as urban when the law came into force in 1988, with strict limits on what can be built there. Whether a plot is affected depends on the official boundary line, plot by plot. Our guide to the coastal law when buying near the sea explains how to check.

Rustic land. Many inland fincas sit on non-developable land, where building and extension rules are far stricter and where the fifteen-year limit for illegal works does not apply. Never assume that a house on rustic land can be legalised or extended.

Flood and fire. Check the plot against the Valencian flood risk plan (PATRICOVA) and the national flood maps, and against the forest fire rules if it borders woodland. These checks can affect insurance and any future building work.

Rentals and the energy certificate

If you plan to let. A holiday rental needs its own checks: the regional tourist registration, the town's planning position and the rules of the community. Spanish law allows a community of owners to limit or ban tourist lets by a three-fifths majority, so read the statutes and recent minutes. Never treat an existing licence as automatically yours.

The energy certificate. The seller must annex a copy of the registered energy certificate and its label to the sale contract. Check the rating and the date, because a certificate is valid for ten years at most, and five for a G rating.

This is an overview of how the checks work, not legal advice; have an independent lawyer review your own purchase before you sign the private contract. The practical rule: ask for the nota simple, the cadastral record, the occupation licence and the community certificate at the offer stage, and do not pay a deposit until your lawyer has read them. The luxury villas on the Costa Blanca North are a good place to start looking.

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Across the coast

Written by Nicolas Strebel.