Building works and planning permission in Spain

Types of Planning Licence in Spain

Planning permission in Spain is managed at the municipal level. There are two main types:

  • Licencia de Obra Mayor: For significant structural works — new builds, extensions, structural changes, demolitions. Requires architect's project and municipal approval. Processing: 3–6 months.
  • Licencia de Obra Menor: For smaller, non-structural works — bathroom, kitchen, windows. Simpler application, faster approval (weeks). No full architect's project required.

A Comunicación Previa system exists in some municipalities for very minor works. Your lawyer can confirm which category applies to your project.

Common Works That Require a Licence

Many property owners are surprised to learn that the following require formal planning permission:

  • Swimming pool construction or enlargement
  • Terrace extensions or enclosures (pergolas with fixed roof)
  • Garden rooms, outbuildings, storage rooms
  • Changes to the building's exterior (facade, windows, balconies)
  • Converting a garage to habitable space
  • Dividing or merging apartments
  • New construction on existing plots

Illegal Works — The Risks

Building without a licence is common on the Costa del Sol. The risks are serious:

  • Fines: Municipal fines can range from thousands to hundreds of thousands of euros.
  • Demolition order: The town hall can order demolition of illegal works at the owner's cost.
  • Problems selling: Illegal works appear on planning records and must be disclosed. Many buyers will not proceed without legalisation.
  • Insurance: Home insurance may be void for unlicensed works.

Legalising Existing Illegal Works

Many illegal works can be legalised retrospectively if they comply with current planning rules. Works more than 4 years old with no open infraction expedient may benefit from a certificado de antigüedad and asimilado a fuera de ordenación certificate.

If works are less than 4 years old and non-compliant, modification or removal may be required. Our lawyers advise on the best strategy for your specific situation.

Frequently Asked Questions

A swimming pool in Mijas typically requires a Licencia de Obra Mayor. You need an architect's project, submitted to the Mijas Ayuntamiento. Processing time: typically 3–6 months. Your project must comply with setback distances and maximum plot coverage rules. After completion, obtain the certificado final de obra from your architect.
As a buyer, you inherit the urban infraction risk. Your lawyer must check planning records and the nota simple for open infraction expedients. If the extension is more than 4 years old with no open expedient, enforcement risk is lower — but it may still affect resale. Negotiate a price reduction or make legalisation a condition of purchase.
Obra mayor requires a full architect's project and municipal approval — for structural works, extensions, and changes of use. Obra menor is for non-structural improvements — simpler, faster, lower fees. The boundary is not always clear, and municipalities interpret categories differently. When in doubt, consult your lawyer before starting.