Doble nacionalidad hispano-portuguesa e internacional: Normativa completa (2026)

1. The Legal Foundation of Portuguese Nationality (<em>Lei da Nacionalidade</em>)

Under Portuguese law (Lei n.º 37/81, as amended by Lei Orgânica n.º 1/2024), Portugal operates under the doctrine of unrestricted plurality of nationalities (pluralidade de nacionalidades).

• Article 8 of Lei n.º 37/81: Portuguese nationality is never conditional upon the renunciation of prior citizenships. The Portuguese state does not require applicants to surrender their foreign passports, nor does the IRN (Instituto dos Registos e do Notariado) notify foreign consulates when Portuguese nationality is granted.
• Article 22: A Portuguese citizen who voluntarily acquires a foreign nationality only loses Portuguese citizenship if they formally declare in writing before a Portuguese consular officer or registrar (Conservatória) that they specifically wish to renounce it.
• The Master Nationality Rule (1930 Hague Convention): While inside Portugal, the Portuguese state considers you exclusively Portuguese. Under Article 3 of the Hague Convention on Certain Questions Relating to the Conflict of Nationality Laws, you cannot invoke the consular protection or diplomatic immunity of your other country of citizenship while physically present on Portuguese territory.

2. Comprehensive Country-by-Country Matrix (2026 Regulatory Status)

• United States: YES (Unrestricted) — US tax filing continues worldwide (FATCA / FBAR). Must enter/leave US on US passport.
• United Kingdom: YES (Unrestricted) — No restrictions; British Nationality Act 1981 applies.
• Canada: YES (Unrestricted) — Fully compatible without notification.
• Australia: YES (Unrestricted) — Section 17 repealed in 2002; full retention. Must enter/leave Australia on Australian passport.
• Germany: YES (Reform 2024) — Staatsangehörigkeitsrecht 2024 abolished Beibehaltungsgenehmigung. No permit required.
• France: YES (Unrestricted) — French Civil Code allows multiple nationalities freely.
• South Africa: CONDITIONAL (Trap) — MUST apply for Permission to Retain BEFORE Portuguese citizenship certificate issuance.
• India: NO (Strictly) — Indian passport revoked; must surrender within 90 days and convert to OCI status.
• China (PRC): NO (Strictly) — Article 9 PRC Nationality Law: automatic loss of citizenship. Hukou cancellation required.
• Russian Federation: PERMITTED — Notification to MVD within 60 days of entry into Russia (Art. 11 Law 138-FZ).
• Ukraine: COMPLEX / TOLERATED — Single nationality principle; de facto tolerated abroad without individual presidential decree.
• Brazil: YES (PEC 16/2021) — Constitutional Amendment 131/2023 unconditionally protects Brazilian citizenship.
• Spain: SPECIAL REGIME — Dual status recognized de facto; 2021 bilateral treaty prevents loss of Spanish nationality.
• Turkey: YES (Notification) — Permitted under Law No. 5901; requires registration (Çok Vatandaşlık Tescili) at Nüfus.
• Israel: YES (Unrestricted) — Fully permitted for naturalised foreign citizens. Must enter/exit Israel on Israeli passport.

3. Granular Legal Breakdown by Jurisdiction

United States of America

• Legal Posture: Fully permitted. The landmark Supreme Court rulings (Afroyim v. Rusk in 1967 and Vance v. Terrazas in 1980) established that an American citizen cannot lose US nationality by naturalising in a foreign state unless they perform the act with the specific, proven intent to relinquish US citizenship.
• Passport Rule: Under Section 215 of the Immigration and Nationality Act (8 U.S.C. 1185), US citizens must use their US passport to enter and exit the United States.
• The Expat Blindspot: Dual citizenship does not relieve Americans of US taxation. The US imposes Citizenship-Based Taxation (CBT), requiring annual filing of IRS Form 1040, FinCEN Form 114 (FBAR), and FATCA Form 8938 regardless of where they reside.

Germany (Deutschland) — The 2024 Historic Breakthrough

• Legal Posture: Fully permitted since June 27, 2024.
• The Reform (Modernisierung des Staatsangehörigkeitsrechts): Prior to 2024, German citizens who naturalised abroad automatically lost their German passport unless they secured an advance Beibehaltungsgenehmigung (Retention Permit) under § 25 StAG. The 2024 reform completely removed § 25 StAG. German citizens can now acquire Portuguese citizenship without any prior application, administrative delay, or risk of forfeiture.

South Africa — The Severe Forfeiture Trap

• Legal Posture: Conditional upon mandatory advance permission.
• Statutory Trap (Section 6(1)(a) of the South African Citizenship Act 88 of 1995): Any South African adult citizen who voluntarily acquires citizenship of another country by naturalisation automatically loses South African citizenship by operation of law.
• The Fix: Before taking the oath or receiving the Portuguese nationality certificate (Assento de Nascimento), the applicant must submit Form DHA-175 and Form DHA-529 to the Department of Home Affairs (or the South African Embassy in Lisbon) to obtain an official Certificate of Retention of South African Citizenship. If this certificate is issued after the Portuguese certificate date, South African nationality is irrevocably lost.

India — Automatic Loss and the OCI Shield

• Legal Posture: Strictly prohibited under Article 9 of the Constitution of India and Section 9 of the Citizenship Act, 1955.
• Immediate Obligation: Upon naturalisation in Portugal, an Indian citizen must surrender their Indian passport to the nearest Indian mission within 90 days (under the Passport Act 1967) and obtain a Surrender Certificate. Travelling on an Indian passport after acquiring foreign citizenship incurs steep monetary penalties.
• The Solution: Former Indian nationals can apply for the Overseas Citizen of India (OCI) card. An OCI card grants lifelong multiple-entry visa-free travel to India, parity with non-resident Indians in economic and educational spheres, and full freedom to live, work, and purchase non-agricultural property in India.

China (People's Republic of China)

• Legal Posture: Strict non-recognition under Article 3 and Article 9 of the PRC Nationality Law.
• Statutory Consequence: Article 9 stipulates that any Chinese national who settles abroad and voluntarily acquires foreign citizenship automatically loses Chinese nationality.
• Consular Reality: Chinese consulates do not issue Chinese visas in a Portuguese passport until the applicant formally presents and cancels their Chinese passport and Chinese National ID card (Hukou cancellation).

Russian Federation

• Legal Posture: Permitted. Russian law distinguishes between двойное гражданство (dual citizenship based on bilateral state treaties, e.g., with Tajikistan) and второе гражданство (possession of another citizenship).
• Federal Law No. 138-FZ (former 62-FZ): A Russian citizen holding a Portuguese passport is regarded by the Russian Federation solely as a Russian citizen.
• Mandatory Notification Rule: Under Article 11 of Federal Law No. 138-FZ, Russian citizens must notify the Main Directorate for Migration Affairs of the Ministry of Internal Affairs (МВД) within 60 calendar days of acquiring foreign citizenship. If the citizen resides permanently outside Russia, the 60-day deadline begins from the moment they first cross the border back into the Russian Federation. Failure to notify within the deadline leads to administrative fines (Art. 19.8.3 KoAP) or criminal prosecution under Article 330.2 of the Criminal Code of the Russian Federation (up to 400 hours of community service or a fine of up to 200,000 rubles).

Ukraine

• Legal Posture: Constitutional principle of single citizenship (Article 4 of the Constitution of Ukraine; Law of Ukraine "On Citizenship of Ukraine").
• De Facto Administration: Acquisition of foreign citizenship does not lead to automatic forfeiture. Ukrainian authorities consider the individual solely a citizen of Ukraine until a formal presidential decree of termination (Указ Президента України про припинення громадянства) is issued. In practice, loss of citizenship is virtually never enforced administratively for private individuals naturalising in EU jurisdictions. Travel to Ukraine must strictly be executed on a valid Ukrainian passport.

Brazil

• Legal Posture: Fully permitted following Constitutional Amendment No. 131/2023 (PEC 16/2021).
• Historical Context: Previously, under Article 12, § 4, II of the Brazilian Federal Constitution, a Brazilian who voluntarily acquired foreign citizenship could be stripped of Brazilian nationality unless the foreign law required it as a condition for residence.
• Current Law: The 2023 amendment eliminated loss of Brazilian citizenship except in cases of explicit, voluntary written renunciation submitted to the Ministry of Justice. Brazilian citizens who acquire Portuguese nationality retain their Brazilian passport and political rights unconditionally.

Spain

• Legal Posture: Special reciprocal relationship. While the Spanish Civil Code (Article 24) normally requires Spaniards to declare their desire to retain Spanish nationality within 3 years of acquiring a foreign nationality, Portugal and Spain signed a bilateral dual nationality treaty in 2021 facilitating dual nationality without renunciation declarations.

Turkey

• Legal Posture: Permitted under Turkish Citizenship Law No. 5901 (Article 44).
• Procedure: Turkish citizens who naturalise in Portugal must submit their Portuguese birth certificate (Assento de Nascimento) and translation to the Turkish Consular Mission or the General Directorate of Civil Registration and Nationality (Nüfus ve Vatandaşlık İşleri Genel Müdürlüğü) to register their multi-citizenship status (Çok Vatandaşlık Tescili). Men of conscription age remain subject to Turkish military service rules unless deferment or exemption is formalized.

4. Interactive Widget: Global Dual Citizenship Compatibility Engine

5. Critical Traps & Cross-Border Legal Realities

Trap 1: The Master Nationality Rule & Consular Protection

Under international law and the 1930 Hague Convention on Certain Questions Relating to the Conflict of Nationality Laws (Article 3), a state may not afford diplomatic protection to one of its nationals against a state whose nationality such person also possesses. Practical Example: If you are a dual US-Portuguese citizen and are detained or questioned by tax, judicial, or administrative authorities in Portugal, the US Embassy in Lisbon cannot intervene on your behalf or assert consular jurisdiction. Within Portuguese borders, you are exclusively Portuguese.

Trap 2: Airport Passport Sequencing

Dual citizens must adhere to a strict border sequence to avoid immigration complications: 1. Departing Portugal / EU: Present your Portuguese passport to SEF/PSP border control (proving legal EU residence and unrestricted exit). 2. Boarding the Airline: Present the passport required to enter your destination country (e.g., US passport for US flights, avoiding ESTA requirements). 3. Arriving at Destination: Present the domestic passport of that country (mandatory under US, Australian, and Russian laws). 4. Returning to the EU: Present your Portuguese passport to airline check-in (clearing Schengen visa checks) and at the EU e-Gates upon arrival in Lisbon or Porto.

Trap 3: The South African "Retention" Sequence

Never schedule your Portuguese citizenship oath or collect your Assento de Nascimento until the physical South African retention certificate has been stamped and delivered. If the Portuguese certificate date precedes the retention stamp, South African citizenship terminates irreversibly.

Guías relacionadas de nacionalidad y fiscalidad