Nationality can be acquired by request, by adoption or by naturalization.

• Acquiring nationality by request:

. Minor or incapable foreigner, whose mother or father acquired Portuguese nationality after his/her birth can acquire Portuguese nationality if he/she declares, through their legal representatives, that he/she wants to be Portuguese and as long as no other circumstances opposing the acquisition of nationality are verified;

. Foreigner married to a Portuguese national for longer than three years or living in a non-marital partnership with a Portuguese national for longer than three years can acquire Portuguese nationality if he/she declares, as a consequence of the marriage or non-marital partnership, to want to be Portuguese as long as no other circumstances opposing the acquisition of nationality are verified;

. Foreigner that had once been Portuguese, lost his/her nationality while a minor or incapable, by effect of a declaration by the person who represented him/her, can once again acquire Portuguese nationality if so declared, when capable, as long as no other circumstances opposing the acquisition of nationality are verified;

Constitute as circumstances opposing the acquisition of nationality by request the lack of effective ties to the national community, sentence in accordance with the law, with prison sentence of three years or more, the exercise of public service without a predominantly technical nature or non-compulsory military service to a foreign State and the existence of danger or threat to national security or defense, by his/her involvement in activities related to the practice of terrorism, under the terms of the law.

• Acquisition of nationality by adoption:

. Adopted foreigner by a Portuguese national, by declaration.

• Acquisition of nationality by naturalization:

. Foreigners who are of majority age, or emancipated, under the Portuguese law, who have legally resided in Portuguese territory for at least six years, who have sufficient command of the Portuguese language and have not been convicted, with a sentence transited (closed case), for a crime liable to a prison sentence of three years or more, and as long as no other circumstances opposing the acquisition of nationality are verified;

. Minors, under the Portuguese law, born in Portuguese territory, children of foreigners, who have sufficient command of the Portuguese language and have not been convicted, with a sentence transited (closed case), for a crime liable to a prison sentence of three years or more and show no danger or threat to national security or defense, by involvement in activities related to the practice of terrorism, under the terms of the law, and that at the time of the request:

– one of the parents has residence in Portuguese territory, regardless of the permit, for at least the five years immediately previous to the request, or 

– the minor has concluded at least one cycle of basic or secondary education;

. Child or young person with less than 18 years of age, hosted in a public institution, cooperative, social or private with a cooperation agreement with the State, resulting from a definite promotion and protective measure applied in a promotion and protection process, under the Protection Law of Children and Young People in Danger, where the Public Ministry is responsible for the promotion of the respective naturalization process;

. Individuals who had Portuguese nationality and that, having lost it, have not since acquired another nationality, as long as they are of majority age, or emancipated under the Portuguese law, have not been convicted, with a sentence transited (closed case), for a crime liable to a prison sentence of three years or more and show no danger or threat to national security or defense, by involvement in activities related to the practice of terrorism, under the terms of the law;

. Individuals born in Portuguese territory, children of foreigners with residence in Portuguese territory, regardless of the permit, at the time of his/her birth and with residence in Portuguese territory, regardless of the  permit, for at least five years, as long as they are of majority age, or emancipated under the Portuguese law, have sufficient command of the Portuguese language and have not been convicted, with a sentence transited (closed case), for a crime liable to a prison sentence of three years or more and show no danger or threat to national security or defense, by involvement in activities related to the practice of terrorism, under the terms of the law;

. Descendants of Portuguese Sefarditas Jews, by showing ties to the Sefaritas community of Portuguese origin, based on objective requisites of ties to Portugal, namely the surname, familiarity with the language, direct or collateral descent, as long as they are of majority age, or emancipated under the Portuguese law, have not been convicted, with a sentence transited (closed case), for a crime liable to a prison sentence of three years or more and show no danger or threat to national security or defense, by involvement in activities related to the practice of terrorism, under the terms of the law;

. Individuals that, not being stateless, had once Portuguese nationality, those descendants of Portuguese, the members of communities of Portuguese ascendance and the foreigners that have served or will be called to serve the Portuguese State or the national community, as long as they are of majority age, or emancipated under the Portuguese law, have not been convicted, with a sentence transited (closed case), for a crime liable to a prison sentence of three years or more and show no danger or threat to national security or defense, by involvement in activities related to the practice of terrorism, under the terms of the law;

. Individuals ascendants of original Portuguese citizens, with residence in Portuguese territory, regardless of the permit, for at least five years immediately prior to the request and as long as the ascendance was established at the moment of birth of the Portuguese citizen, as long as they are of majority age, or emancipated under the Portuguese law, have sufficient command of the Portuguese language and have not been convicted, with a sentence transited (closed case), for a crime liable to a prison sentence of three years or more and show no danger or threat to national security or defense, by his/her involvement in activities related.

Constitute as circumstances opposing the acquisition of nationality by request the lack of effective ties to the national community, sentence in accordance with the law, with prison sentence of three years or more, the exercise of public service without a predominantly technical nature or non-compulsory military service to a foreign State and the existence of danger or threat to national security or defense, by his/her involvement in activities related to the practice of terrorism, under the terms of the law.

For more information please see, “How to get information on requesting Portuguese nationality?”.