Building works and planning permission in Spain

Types of Planning Licence in Spain

In Spain, planning permission is managed at the municipal level — so for properties in Mijas, Fuengirola, or Marbella, you apply to the respective Ayuntamiento (town hall). There are two main types of permission:

  • Licencia de Obra Mayor (Major Works Licence): Required for significant structural works — new builds, extensions that increase surface area, structural changes, demolitions, and changes of use. Requires an architect's project, detailed technical plans, and municipal approval. Processing takes 3–6 months in Mijas typically.
  • Licencia de Obra Menor (Minor Works Licence): For smaller, non-structural works — bathroom refurbishment, kitchen renovation, replacing windows, minor interior reforms. Simpler application process, lower fees, faster approval (weeks rather than months). Does not require a full architect's project, though a technical description of works is needed.

Additionally, a Comunicación Previa (Prior Notification) system exists in some municipalities for very minor works — you notify the town hall before starting rather than requesting approval. Your lawyer can confirm which category applies to your specific project in Mijas.

Common Works That Require a Licence

Many property owners on the Costa del Sol are surprised to learn that the following works require formal planning permission in most municipalities:

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

Illegal Works (Obras Sin Licencia) — The Risks

Building without a licence or beyond what a licence permits is extremely common on the Costa del Sol — particularly for pools, terraces, and outbuildings built in earlier decades when enforcement was lax. The risks of illegal works are serious:

  • Fines: Municipal fines for urban infraction can range from a few thousand to hundreds of thousands of euros depending on the severity and the value of the works.
  • Demolition order: The town hall can order the demolition of the illegal works at the owner's cost.
  • Problems selling: Illegal works appear on the town hall's records and must be disclosed in the nota simple. Buyers' lawyers will flag them. Many buyers will not proceed without legalisation or a significant price reduction.
  • Insurance issues: Home insurance may be void for works carried out without licence.

Legalising Existing Illegal Works

Many illegal works can be legalised retrospectively (legalización de obras) if they comply with the current urban planning rules for the area. The process involves obtaining a certificado de antigüedad (certificate confirming the works are more than 4 years old — the statute of limitations for enforcement in Andalucía for most works) and then applying for an asimilado a fuera de ordenación certificate, which regularises the situation without full compliance.

If the works are less than 4 years old and non-compliant, full legalisation may require modifying or removing them. If they are more than 4 years old but the breach is recorded in municipal records (expediente de infracción urbanística), the statute of limitations may not apply. Our property lawyers in Mijas advise on the best legal strategy for your specific situation.

Frequently Asked Questions

A swimming pool in Mijas typically requires a Licencia de Obra Mayor — even for a relatively modest pool. You will need an architect to prepare a project, submit it to the Mijas Ayuntamiento, and wait for approval. Processing time in Mijas is typically 3–6 months. Your project must comply with the setback distances and maximum coverage rules for your plot. Once approved and the pool is built, you need to obtain the certificate of completion (certificado final de obra) from your architect. We strongly recommend engaging a lawyer before starting to ensure compliance with your specific plot's planning conditions.
As a buyer, you inherit the urban infraction risk with the property. Your lawyer must check the town hall planning records and the nota simple for any open infraction expedients. If the illegal extension is more than 4 years old and has no open expedient, the practical enforcement risk is lower — but it may still affect the property's value and resale. You should negotiate a price reduction reflecting the legalisation cost, or make legalisation (or a price adjustment) a condition of purchase. Never complete a property purchase with illegal works without taking specific legal advice first.
Obra mayor requires a full architect's project, detailed plans, and municipal approval — used for structural works, new builds, extensions, and changes of use. Processing takes months. Obra menor is for non-structural improvements (kitchen, bathroom, windows) — simpler application, faster approval, lower fees. The boundary between them is not always clear, and different municipalities interpret the categories differently. When in doubt, consult your lawyer and architect before starting any works.