Due diligence checklist for buying in Spain

Why Due Diligence Matters More in Spain Than You Think

Spain's property market is one of Europe's most active, attracting hundreds of thousands of foreign buyers every year. But unlike other European markets, Spain has a complex layer of official data — cadastral records, flood maps, soil classification, radon zones, noise maps — that most buyers never check. This guide walks through every official check worth running before making an offer, using only public Spanish data sources.

1. Verify the Cadastral Reference (Referencia Catastral)

The referencia catastral is Spain's unique property identifier — a 20-character alphanumeric code that unlocks all official data for a property. The first 14 characters identify the parcel (land plot); the last 6 identify the specific unit (apartment, house, garage). Always ask the seller or agent for the full 20-character reference. You can cross-check it on the Sede Electrónica del Catastro (catastro.meh.es) to verify the property's official surface area, year of construction, use, and ownership history.

Full guide: What is the cadastral reference →

• Verify surface area matches what's advertised (discrepancies of 10-20% are common)
• Check declared year of construction (affects renovation obligations and structural expectations)
• Confirm the property use classification matches the intended use

2. Request the Nota Simple from the Land Registry

The nota simple from the Registro de la Propiedad is the definitive document showing who legally owns the property and what charges, mortgages, or liens are registered against it. It costs around €9 and can be requested online via the Colegio de Registradores. Key things to check:

Full guide: The ‘instant’ nota simple myth →

• Owner name matches the seller's identity document
• Outstanding mortgages (the seller must cancel these at closing)
• Urban charges, easements, or rights of way affecting the property
• Whether the property is registered at all (some properties in rural Spain are not)

3. Check the SNCZI Flood Map

Spain's SNCZI (Sistema Nacional de Cartografía de Zonas Inundables), managed by MITECO, classifies every plot in Spain by flood return period: T10 (high frequency), T100 (medium) and T500 (low). Properties in high-risk zones can face restricted insurance, mortgage conditions, and urban development limitations. Coastal properties also face marine flood risk from storms, mapped separately. Always verify with the official SNCZI viewer or via a Hogarfax report.

Full guide: River and coastal flood risk in Spain →

4. Check Radon Risk by Municipality

Radon is an invisible, odourless radioactive gas that seeps from granite and certain soils. The Spanish Consejo de Seguridad Nuclear (CSN) classifies all Spanish municipalities into radon risk zones. Galicia, parts of Extremadura, Castilla y León and inland Andalucía have the highest concentrations. For properties in Zone 2 or 3, budget for a professional radon measurement (€100-200) and potential mitigation works (€1,500-5,000).

Full guide: Radon home risk in Spain →

5. Verify Urban Classification (Clasificación Urbanística)

Spain's SIU (Sistema de Información Urbana) classifies land as urban, developable or non-developable. This determines what can be built, extended or renovated on the plot. Rural or 'rustic' properties are particularly exposed to this risk — what looks like a charming farmhouse may technically be an illegal construction on non-developable land, with no right to rebuild if damaged. Always request the certificado urbanístico from the municipality before signing.

Full guide: Land classification and the SIU →

• Suelo urbano: fully urban, standard residential rights
• Suelo urbanizable: planned for development, may have restrictions
• Suelo no urbanizable (rústico): strict limits on construction and renovation

6. Check for Coastal or Riverside Restrictions (DPH/DPMT)

Properties within 100 metres of the coastline may fall within the Dominio Público Marítimo-Terrestre (DPMT) regulated by Spain's Ley de Costas. Properties near rivers and streams may fall within the Dominio Público Hidráulico (DPH). Both zones impose strict limits on construction, renovation and use. The IGN and Demarcaciones de Costas publish these boundaries officially.

Full guide: Public water and coastal domains (DPH/DPMT) →

7. Verify the Building Inspection (ITE) Status

Buildings over 50 years old are required to have a Inspección Técnica de Edificios (ITE) — a structural and conservation inspection. An unfavourable ITE report means the building has prescribed remediation works that the community of owners must fund. As a buyer, you inherit a proportional share of these costs. Always ask for the last ITE report and its outcome before buying in an older building.

Full guide: Building inspection: ITE and IEE →

8. Benchmark the Price Against Official Transaction Data

Asking prices in Spain can be significantly above actual closed prices. The Colegio de Registradores de España publishes quarterly statistics on actual notarial transaction prices by province, municipality and property type. This is the most reliable benchmark for real market prices — not portals, which only track asking prices. A Hogarfax report includes the official price reference for the municipality to help you negotiate with evidence.

Full guide: Real vs asking price in Spain →

Full guide: Home purchase calculator →