Two straight answers before anything else. This is not a directory, and unlike our French page it is not a checker either, because Spain has no open register of building companies to check against. What it is: the question that decides which guarantees your job comes with, and the one case where a document must be on the table before the notary.
There is no freely queryable state register of building companies in Spain of the kind France has, so this page cannot offer you the live check that the French one does. What exists is a company register you pay to search, and a construction sector register held per region. Neither is something we can run for you from here, and pretending otherwise would be worse than saying so.
For France we can do better, because three French state registers are open to anyone: checking a French builder. That difference is worth knowing if you are still choosing a country.
Spanish building law does not cover every job, and which side of that line your work falls on decides what paperwork exists at all. Read these two before you write your list of demands.
The building law does not cover every job. It covers new construction, and it covers work on an existing building only where that work changes its architectural configuration: a total intervention, or a partial one that essentially alters the external composition, the volume or the structural system, or that changes what the building is used for. A bathroom refit is not on that list; taking out a load-bearing wall is.
Todas las intervenciones sobre los edificios existentes, siempre y cuando alteren su configuración arquitectónica, entendiendo por tales las que tengan carácter de intervención total o las parciales que produzcan una variación esencial de la composición general exterior, la volumetría, o el conjunto del sistema estructural, o tengan por objeto cambiar los usos característicos del edificio.A listed or protected building is treated more strictly: a total intervention always counts, and partial ones count as soon as they touch the protected elements. If your house carries any heritage protection, assume you are inside the law rather than outside it.
Obras que tengan el carácter de intervención total en edificaciones catalogadas o que dispongan de algún tipo de protección de carácter ambiental o histórico-artístico, regulada a través de norma legal o documento urbanístico y aquellas otras de carácter parcial que afecten a los elementos o partes objeto de protección.The ten year guarantee is tied to buildings whose main purpose is housing, which in practice means building homes rather than renovating one. That is the opposite of what a British owner who read up on France expects, and it is the single most useful thing on this page.
La garantía contra daños materiales a que se refiere el apartado 1.c) del artículo 19 de esta Ley será exigible, a partir de su entrada en vigor, para edificios cuyo destino principal sea el de vivienda.One case where you should insist on it, and it is a buying case rather than a building one. Someone who built their own single home is exempt, but if they sell within the ten years they must take the guarantee out for the remaining time, and a deed cannot be authorised or registered without proof of it. If you are buying a self built house, that is a document to ask for before the notary, not after.
A estos efectos, no se autorizarán ni inscribirán en el Registro de la Propiedad escrituras públicas de transmisión "inter vivos" sin que se acredite y testimonie la constitución de la referida garantía, salvo que el autopromotor, que deberá acreditar haber utilizado la vivienda, fuese expresamente exonerado por el adquirente.British owners hear ten year guarantee and assume that is the whole story. The law sets out three, each for a different kind of defect, and the shortest one can be replaced by the developer holding money back instead.
Source checked on 2026-08-18: BOE, Ley 38/1999 de Ordenación de la Edificación, texto consolidado.
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The other two questions that decide what a Spanish job really costs: which tax rate applies and whether you need permission.
No, and we are not going to build one. This site does not sell leads, which is what a directory of that kind runs on. Nor can we offer the live company check we run for France: Spain has no equivalent open register.
Not automatically, and this is where advice written for France misleads people. The Spanish ten year guarantee attaches to buildings whose main purpose is housing, which in practice means building homes rather than renovating one. Asking for it on a bathroom refit is asking for a document that need not exist.
When you are buying rather than building. Someone who built their own home is exempt from the guarantee, but if they sell within ten years they must take it out for the remaining period, and the deed cannot be authorised or registered without proof. Ask for that before the notary appointment, not after.