Dual Citizenship Explained

Yes. The United States generally allows dual citizenship. If you naturalize as a U.S. citizen, you are not required to formally give up your citizenship in your country of origin, and U.S. law does not automatically strip you of U.S. citizenship if you also hold citizenship elsewhere. Whether you can actually keep your other citizenship, however, is decided by that other country's laws — not by the United States.

What the naturalization oath actually requires

People are often confused by the wording of the Oath of Allegiance that every naturalization applicant must take. The oath includes a line stating that the applicant "absolutely and entirely renounce[s] and abjure[s] all allegiance and fidelity to any foreign prince, potentate, state, or sovereignty" of which they were previously a citizen or subject.

Read literally, this sounds like you must give up your other citizenship. In practice, it does not work that way. U.S. Citizenship and Immigration Services (USCIS) does not require applicants to take any additional legal steps — such as filing paperwork with a foreign government — to renounce a prior nationality as a condition of naturalizing. The oath is a declaration of primary loyalty to the United States; it is not, by itself, a mechanism that cancels your other citizenship. For the official language and USCIS's explanation of the oath, see the USCIS naturalization oath page and the USCIS Policy Manual, Volume 12, Part J, Chapter 2, which explains the oath in detail. Separate provisions in that same Part J of the Policy Manual address the limited modifications and waivers of the oath available to people with certain religious or conscientious objections.

Why the "other side" is what really matters

Citizenship is a matter of each country's own law. The United States cannot make another country's citizenship disappear, and it cannot force another country to let you keep it. That means your actual dual-citizen status depends entirely on the rules of your other country of citizenship:

• Some countries permit dual or multiple citizenship freely and will not treat your U.S. naturalization as a problem.
• Some countries automatically revoke their citizenship when a citizen voluntarily naturalizes in another country, unless the person applied in advance for permission to keep it.
• Some countries require an affirmative application or fee to retain citizenship after naturalizing elsewhere, or to formally renounce it if you want to give it up.
• Some countries do not allow renunciation at all, or make it extremely difficult, which can matter for people who want to shed an old citizenship rather than keep it.

Because these rules vary by country and change over time, the only reliable way to know your specific situation is to check with your other country's embassy or consulate, or its equivalent of a nationality/interior ministry, before and after you naturalize.

U.S. citizens who acquire a second citizenship (not just immigrants)

The dual-citizenship question also comes up in the other direction: a U.S. citizen by birth who marries a foreign national, has ancestry in another country, or is naturalized abroad may become eligible for a second citizenship. Longstanding State Department policy is that acquiring a foreign citizenship, by itself, does not cause loss of U.S. citizenship. Losing U.S. citizenship (expatriation) generally requires a person to commit a specific act listed in the Immigration and Nationality Act (such as formally renouncing before a U.S. consular officer) with the intent to give up U.S. citizenship. Simply obtaining another passport does not meet that standard. The State Department's current explanation is at its Dual Nationality page.

Passports and entry/exit rules

Dual citizens should know a few practical passport rules:

• U.S. law requires U.S. citizens to enter and leave the United States using a valid U.S. passport (with narrow exceptions), even if you also hold another passport.
• When traveling in your other country of citizenship, that country may require or expect you to enter and exit using its passport rather than your U.S. one.
• The U.S. government generally treats dual nationals as U.S. citizens while they are in the United States, and it can be limited in how much it can assist you if you run into legal trouble in the other country of which you're a citizen — because that country may treat you as its own national first. See the State Department's dual nationality guidance linked above for more on this.

Taxes

This is one of the most commonly misunderstood parts of dual citizenship. The United States taxes its citizens on worldwide income regardless of where they live — this is different from most other countries, which generally tax based on residency. That means a dual citizen living outside the United States may still have U.S. federal tax filing obligations, in addition to whatever tax obligations exist in the other country. There are treaties, exclusions, and credits that can reduce or eliminate double taxation in many cases, and separate reporting requirements can apply to foreign bank accounts and financial assets. Because tax rules, thresholds, and treaty provisions change and are fact-specific, this article does not state specific dollar figures or forms — consult the IRS's international taxpayer resources or a qualified tax professional familiar with cross-border filing for your situation.

Other practical issues to be aware of

• Military service: Some countries require citizens (including dual citizens) to register for or perform military service. This is governed entirely by that country's law.
• Voting: Some countries restrict voting or certain civic rights for citizens who also hold another nationality; others do not.
• U.S. government employment and security clearances: Holding dual citizenship, or even just possessing a foreign passport, can be relevant to eligibility for certain federal jobs or security clearances and may need to be disclosed and addressed during that process.
• Using a foreign passport after naturalizing: Simply holding or occasionally using a foreign passport does not, by itself, jeopardize your U.S. citizenship.

What to do

1. Before naturalizing, contact your home country's embassy, consulate, or nationality authority to ask whether naturalizing as a U.S. citizen will affect your existing citizenship there, and whether you need to take any steps to preserve it.
2. Confirm current U.S. procedures directly with USCIS (uscis.gov) before you file, since forms, instructions, and the naturalization interview process can be updated.
3. Keep both passports valid if you intend to remain a dual citizen, and remember the rule that you must use your U.S. passport to enter and leave the United States.
4. Get tax guidance from the IRS's international/nonresident resources or a cross-border tax professional if you have income, accounts, or assets outside the United States.
5. If you ever want to formally renounce either citizenship, understand that U.S. renunciation is a serious, generally irrevocable step done in person before a U.S. consular or diplomatic officer abroad, with significant legal and tax consequences — this is very different from simply not using a passport.
6. If your situation is complicated — for example, you are in the middle of an immigration case, have a pending naturalization application, or your home country has unusual citizenship-loss rules — talk to a qualified immigration attorney or a Department of Justice–accredited representative before making decisions.

Beware of notario and immigration-fraud scams

People offering to "guarantee" dual citizenship outcomes, sell shortcuts, or act as a notario público without proper legal authorization are not a substitute for a licensed immigration attorney or a DOJ-accredited representative. Only USCIS (uscis.gov), the immigration courts (justice.gov/eoir), and the State Department (travel.state.gov) are official sources for U.S. immigration and citizenship information. Never pay someone for immigration help unless you have verified they are actually authorized to provide it.

This article is general information, not legal advice, and does not create an attorney-client relationship. Immigration and citizenship rules are fact-specific and can change — verify current procedures with USCIS, the State Department, or a qualified immigration attorney before acting.