One of the ways to obtain Portuguese nationality is through marriage or de facto union for more than three years, a situation provided for in Article 3 of the Portuguese Nationality Law (Law No. 37/81, of October 3).
There are situations in which the citizen of Portuguese nationality married before the authorities of another country, with a foreign or Portuguese person. In this case, the marriage certificate must be transcribed to the Portuguese civil registry so that it is valid here.
The request for marriage transcription is made at a consular post or at the Civil Registry Office in Portugal and must be accompanied by the necessary documents.
The transcription of the marriage can be done at any time after the union is made official abroad.