Dual citizenship (also known as dual nationality) is when someone is a legal citizen of two countries at the same time. But what does dual citizenship mean in practical terms?

It means you can hold two passports, enjoy the rights and benefits of two countries, and access broader opportunities for work, travel, and investment. For many, it’s a strategic way to secure global mobility and long-term security.

This guide explains what dual citizenship is, how to get it, the benefits and disadvantages, travel rules for dual passports, and the list of countries that allow or restrict this status.

What is dual citizenship?

People walking alongside colorful houses in Wroclaw, Poland - dual citizenship

Dual citizenship (also called dual nationality) is when a person is legally recognized as a citizen of two countries simultaneously.

This means that, if you have a foreign nationality, you have both rights and obligations to fulfil in both countries. These include the right to live, work, and study in each country, cast a vote where applicable, and the duty to follow the laws of each country.

As a dual citizen, you may be issued a second passport (so then you have one from each country), and you must use them according to each country’s entry/exit rules.

Dual citizenship can arise through being born in a country (jus soli), descent from a citizen parent (jus sanguinis), naturalization, marriage, or, in special cases, investment.

Citizenship doesn’t expire, but passports do. Some countries restrict multiple citizenship or require renunciation when you naturalize elsewhere.

According to the Global Citizen Solutions’ Global Intelligence Unit’s “The Transformation of Citizenship” report, over 76% of countries now allow dual citizenship, up from 33% in 1960. This reflects its shift from being a political identity you associate yourself with to being a strategic way to increase your travel mobility and gain access to business opportunities.

What are the benefits of dual citizenship?

Woman's hands holding up passports against a white wall - dual citizenship

Dual citizenship offers individuals practical advantages across various areas:

  • Two passports and easier travel: Hold valid passports from both countries for broader visa-free access, simpler routing across borders, and fewer visa obligations.
  • Live, work, and study in either country: Residency rights let you relocate without needing specific permits, access local job markets, and enroll in education (often at domestic tuition rates).
  • Access to public systems: Depending on each country’s rules, you may qualify for healthcare, social benefits, and pensions as a citizen.
  • Family security and reunification options: Dual citizenship status can make sponsoring spouses and/or children easier and offers a legal fallback for families who want to relocate abroad if needed.
  • Property ownership and investment flexibility: Purchasing or investing in international real estate, and making investments in either country often come with fewer restrictions when you’re a citizen.
  • Entrepreneurship and employment advantages: Start a business, bid on contracts, or take roles that are citizens-only, all without the need to apply for work permits.
  • Consular assistance and crisis resilience: Access consular support from either nation abroad and retain a Plan B passport during political, economic, or public-health disruptions.
  • Cultural connection and identity: Maintain language, heritage, and community ties across borders while giving children multi-country roots.

What are the obligations that come with dual nationality?

Although foreign citizenship comes with many benefits, it also entails responsibilities in both countries. Requirements vary by nationality law, but expect some or all of the following:

  • Passport-use rules (border formalities): Many countries require citizens to enter and exit on their own passport. If you hold a dual passport, be prepared to use the passport of the country you’re entering/exiting and carry both when itineraries involve both countries.
  • Taxes and financial reporting: You may have tax filing and reporting obligations to one or both countries (and sometimes to local/state authorities). Depending on the country pair, you might need to file annual returns, disclose offshore banking/financial accounts, and document foreign assets. Tax treaties, credits, or exclusions can help avoid double taxation, but you’re responsible for compliance and record-keeping.
  • Military, jury, and civic duties: Some countries impose compulsory service, jury duty, or other civic obligations on citizens, including dual nationals. Exemptions, deferments, or age limits can apply, but they’re country-specific, so verify before embarking on long stays.
  • Residence, registration, and address reporting: Certain countries require citizens to register domestically, report address changes, or maintain valid national IDs. Long-term stays might trigger population-register or municipal reporting requirements.
  • Name, identity, and civil-status consistency: Applications based on descent often require exact matches across birth/marriage certificates. Keep apostilles, certified translations, and consistent spellings/dates to avoid delays or future challenges renewing passports or registering children.
  • Public office, professions, and security clearances: Some roles (public office, sensitive professions, security clearances) restrict or scrutinize dual and multiple citizenship.
  • Property ownership and currency controls: While citizenship can ease property purchases, some countries restrict land categories (for example, when it comes to agricultural property or border zones). Separate currency controls or cross-border reporting may apply to transfers, investments, or inheritances.
  • Consular protection limits: When you’re in Country A, its authorities may treat you solely as a citizen of A, limiting what Country B’s consulate can do. This means you have to plan travel and legal needs with that in mind.
  • Law conflicts and enforcement: Dual nationals must follow the legal systems in both countries. Conflicts can arise on issues like family law, custody, inheritance, or sanctions. If laws collide, local law where you’re present usually prevails.
  • Renunciation and loss scenarios: While citizenship doesn’t expire, it can be renounced (voluntarily) or lost/revoked under specific laws (for example if authorities detect fraud in your application). Some countries don’t allow multiple citizenship and may require you to give one up to naturalize elsewhere.

What are the travel and border rules when using two passports?

Which passport do you use where?

As a rule of thumb, use the passport of the country you’re entering and leaving. Many countries require their own citizens to enter/exit on that country’s passport. As a precaution, keep both passports valid and easily accessible.

Trip itineraries that involve both countries

If your trip starts in Country A, connects through a third country, and ends in Country B (of which you’re also a citizen), you may show Passport A at departure and Passport B on arrival.

Match tickets, visas, and APIs (Advanced Passenger Information), a system whereby airlines collect and transmit passenger data to border control agencies before a flight’s departure to improve border security and speed up immigration. You’ll need the relevant document to present at each leg.

Visas, eTAs, and pre-clearance

Apply for any required visa/eTA using the same passport you’ll use to enter that destination. If you switch documents mid-journey, carriers or border systems can’t always match your records.

Expired or soon-to-expire passports

Since citizenship doesn’t expire but passports do, it’s important to maintain validity throughout and renew well in advance. Some destinations require 3 to 6 months’ validity past entry. If one passport expires, you may still travel on the other where eligible, but renew promptly to keep your options open.

Children and traveling as a family

Ensure children who qualify for both citizenships hold their own passports as required, and that names/dates match your civil records. For one-parent travel, carry any consent letters or custody documents the route may require.

Lost or stolen passport

Report the loss and contact the relevant embassy/consulate for emergency travel documentation. Keep digital copies of biodata pages and key civil records to speed replacement.

Name and data consistency

Keep names, dates of birth, and birthplaces consistent across both passports and civil records. If you’ve had a legal name change, update both countries’ documents to reduce check-in/immigration issues.

Dual Citizenship Taxes and Financial Reporting Obligations

Dual citizens are subject to the tax and reporting rules of both countries. The exact outcome depends on the country pair, tax treaties, and your personal situation.

  • Annual filing: You may need to file tax returns in one or both countries, even if no tax is ultimately due.
  • Worldwide income: Some countries tax residents/citizens on worldwide income; others use territorial or remittance-based systems.
  • Double-tax relief: Tax treaties, credits, and exemptions (where applicable) often prevent double taxation but require proper elections and documentation.
  • Foreign accounts: Expect potential foreign account disclosures (e.g., bank, brokerage, pensions) plus documentation for foreign assets or companies.
  • Good practice: Track deadlines, keep organized records (income, cost basis and foreign taxes paid), and seek qualified advice for complicated cross-border cases.

How to get dual citizenship?

There are several pathways to acquire a foreign passport, and the eligibility requirements vary depending on the country. Here are the most common routes to having more than one nationality:

Citizenship by birth

Countries with birthright citizenship laws, like the U.S. and Canada, grant citizenship to anyone born on their soil, except for children of foreign diplomats or certain exempt categories.

A child born in the U.S. to foreign parents may hold dual nationality if the parents’ country also recognizes citizenship by descent.

Citizenship by descent

Many nations, including Italy, Ireland, and Poland, offer citizenship by descent if you have parents or grandparents (and sometimes great-grandparents) from that country.

Example:

  • Italy: As of 2025, eligibility is generally limited to those with an Italian parent or grandparent (claims through great-grandparents are no longer typical under recent reforms).
  • Ireland: Permits citizenship through a grandparent born in Ireland via the Foreign Births Register.
  • Poland: Allows claims if Polish citizenship was continuously passed down in the family line, subject to documentation.

Citizenship by naturalization

Citizenship by naturalization after living in a country for a set period and meeting criteria like language proficiency and good character.

Residency periods for citizenship by naturalization vary, for example:

  • Portugal: Currently 5 years, with a 2025 proposal under discussion to extend this to 10 years (or 7 years in some drafts) but it’s not yet in effect.
  • Argentina: Requires only 2 years of continuous legal residence before applying.

Some countries require renunciation of prior citizenship, but many now accept dual nationality.

Citizenship by marriage

This is the process by which foreigners can get citizenship in a country by marrying a local citizen.

Examples:

  • France: Allows citizenship after four years of marriage (five if you haven’t lived continuously in France or your spouse wasn’t registered abroad).
  • Mexico: Citizenship by marriage is available after two years of marriage and residence in Mexico.

Citizenship by Investment (CBI)

Citizenship is given in exchange for a significant financial contribution, typically through real estate, government bonds, or donations to a national fund.

Examples:

Citizenship by Investment is often processed in around 3 to 6 months, making it one of the fastest legal routes to dual citizenship.

Always check whether all involved countries allow dual citizenship, as some (such as Japan) require you to choose one nationality by a certain age or renounce the other upon naturalization.

American flag hanging from a skyscraper - dual citizenship

Yes, U.S. law allows dual citizenship.

Americans are not required to renounce U.S. citizenship when acquiring another nationality, and becoming a U.S. citizen through naturalization does not automatically revoke your original citizenship, unless your home country prohibits dual nationality or requires you to renounce your original citizenship.

According to the U.S. Department of State, dual citizens must meet the obligations of both countries. For Americans, this means filing annual tax returns on worldwide income even if living abroad, complying with military service requirements if the other country has conscription, and being aware that certain U.S. government positions may be off-limits due to security clearance restrictions.

While holding two passports is permitted, U.S. citizens must exclusively use their American passport when entering or leaving the United States.

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How Can Global Citizen Solutions Help You?

Global Citizen Solutions is a boutique migration consultancy firm with years of experience delivering bespoke residence and citizenship by investment solutions for international families. With offices worldwide and an experienced, hands-on team, we have helped hundreds of clients worldwide acquire citizenship, residence visas, or homes while diversifying their portfolios with robust investments. 

We guide you from start to finish, taking you beyond your citizenship or residency by investment application. 

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