In Article 30, the Constitution establishes that Mexican nationality is acquired by birth or by naturalisation. Mexican legislation applies the principles of ius soli and ius sanguini for acquiring nationality by birth.
Mexicans by birth are:
- those born in the territory of the Republic, regardless of the nationality of their parents;
- those born abroad, who are children of a Mexican father or mother born in the national territory, or Mexicans by naturalization;
- those born on board Mexican vessels or aircraft, whether warships or merchant.
Mexicans by naturalisation are:
Foreigners that obtain from the Ministry of Foreign Affairs a letter of naturalisation, under one of the following events, and who satisfy the other requirements established by the nationality act and its regulation:
- Have resided in the MexicanRepublic for five years or more with a migration document that authorises their residency;
- Have resided in the Mexican Republic for two years or more with a migration document that authorises their residency, provided that they are: a direct line descendant of a Mexican by birth, have Mexican children by birth, or are natives of a Latin American or Iberian Peninsula country;
- Have provided distinguished services to the nation;
- Have contracted marriage with a Mexican man or woman, and possess marital domicile within the national territory for two years or more, prior to the application.
Likewise, Article 37 of the Constitution defines that no Mexican by birth may be deprived of his/her nationality, and that Mexican nationality by naturalisation will be lost due to voluntary acquisition of a foreign nationality, by pretending to be a foreigner on any public instrument, by using a foreign passport, or by using nobility titles that imply submission to a foreign state, and for residing during five continuous years abroad. On the other hand, the Nationality Act (1998) recognises non-loss of Mexican nationality just by mere acquisition of any other nationality.
Articles 34 to 38 of the Constitution establishes that men and women are citizens of the Republic that, having the status of Mexicans (by birth or by naturaliSation), have reached 18 years of age.
Article 37 defines that Mexican citizenship is lost upon acceptance or use of nobility titles of foreign governments; by providing voluntarily official services to a foreign government without the permission of the Federal Congress or its Permanent Commission; by acceptance or use of foreign decorations without the permission of the Federal Congress or its Permanent Commission; for admitting from the government of another country titles or functions without prior consent of the Federal Congress or its Permanent Commission, exempting literary, scientific, or humanitarian titles that can be accepted freely; for assisting, against the Nation, a foreigner or foreign government, in any diplomatic claim or before an international court, and in other cases set forth by law.