Building permits in Portugal: licence, prior communication or exempt
Under the national building law (RJUE), most works that change a building from outside need a licence. A smaller group needs only a prior communication, and some works need nothing at all.
The three routes
- Licence (licença): the default route for building, altering or extending, for subdivisions, for earthworks that reshape land, and for demolition (art 4).
- Prior communication (comunicação prévia): replaces the licence in a short list of cases. These are areas where a detail plan, execution unit or subdivision already fixes the design, consolidated urban zones where the result is no taller than the usual facade height on that street, and swimming pools linked to a main building. Where prior communication applies, you cannot choose a licence instead.
- Exempt (isento): no licence and no prior communication, for the works in articles 6 and 6-A. Even then, tell the council at least 5 days before work starts, except for conservation work done only inside.
What is exempt
Article 6 exempts conservation work (repair, restoration and cleaning that keeps a building as built), interior alterations that change nothing outside and do not affect stability, reconstruction, the demolition of illegal buildings, and the splitting off of a single plot (destaque) under set conditions.
Article 6-A adds the works of minor urbanistic relevance (obras de escassa relevância urbanística):
- Outbuildings up to 2.2 m high, or the eaves height of the main building's ground floor, with an area of 10 m² or less, not facing a public road.
- Fence walls up to 1.8 m not facing a public road, and retaining walls up to 2 m or that do not significantly change ground levels.
- Garden greenhouses under 3 m high and up to 20 m².
- Small works to arrange the grounds around a building, if they do not affect public land.
- Leisure equipment tied to the main building and smaller in area than it.
- Solar panels, energy storage units and solar water heaters within the roof area and 1 m above the building height, and small wind generators up to 4 m above the building with a rotor radius of 1.5 m or less, after notifying the council.
- Replacing exterior finishes, roof coverings or window frames with ones that improve energy efficiency and look identical to the original.
- Demolishing any of the above.
Heritage and restricted areas
The minor-works exemptions do not apply to listed buildings, to buildings in the protection zone of a listed building, or to buildings inside listed groups or sites. The one exception is replacing window frames for energy efficiency, which stays exempt in protection zones. Works on listed buildings, and building, extending, altering the outside of or demolishing in a protection zone, need a licence. Upkeep of a listed building is exempt only with a favourable opinion from the heritage authority. Building in an area under an easement or public-utility restriction also needs a licence unless a plan already covers the restrictions. Removing facade tiles (azulejos) always needs a licence.
Changing a building's use
Changing the use of a building or flat, for example turning a garage into a home, needs a filing with the council. It is a prior communication with a deadline (comunicação prévia com prazo) if no licensed works came first, and a plain prior communication after licensed works.
Your council can add detail
Each council can list further minor works in its own regulation, and it sets fees, colours and aesthetic rules where the law lets it. Your plot is also bound by the local plan, so always check with your council before you start. Exempt work must still follow plans, easements, technical rules and heritage protection.
Which version of the law
These pages follow the RJUE as republished in the Annex of Decreto-Lei 108/2026 of 29 May 2026, with the corrections of Declaração de Retificação 29-A/2026. It came into force on 1 October 2026 (Decreto-Lei 155-B/2026) and applies to procedures started after that date.
This site is independent and is not legal advice. Check with the official source before you act.