Does the US Recognize Dual Citizenship? What the Law Actually Says

Written by the Ellis Porter content team. This article has not been reviewed by an attorney. It is general information, not legal advice.

In plain English: US law permits dual citizenship, even though the government does not formally encourage it and does not require you to prove you have given up another nationality. You can become a US citizen through naturalization while keeping citizenship in another country, but whether the other country lets you keep its citizenship is governed by that country’s own law, not US law. The naturalization oath asks you to renounce foreign allegiances as a matter of loyalty, which is different from a legal requirement to surrender a second passport. Because the rules on both sides interact, the practical answer for any one person depends on the two countries involved and the specific facts.

Can you keep both citizenships? The short answer

If you want to become a US citizen without giving up the citizenship you already have, you are asking the question we hear most often. The good news is that US law leaves the door open. Here is how it works in plain terms.

Dual citizenship (also called dual nationality) means you are legally a citizen of two countries at once. Here is the part that surprises people. US law permits dual citizenship, does not formally encourage it, and does not require a naturalizing citizen to prove they have given up another nationality. As policy, the US does not formally encourage dual citizenship, but it does not prohibit it either.

So does the US recognize dual citizenship? Yes, the US allows it. There is no US law that forces you to pick just one. You can become a US citizen through naturalization while keeping citizenship in another country, but whether the other country lets you keep it is governed by that country’s own law, not US law.

The US side: permitted, not required to renounce

When you become a US citizen through naturalization, you take an oath of allegiance that asks you to renounce allegiance to foreign states as a matter of loyalty. That language sounds like it should end any other citizenship. But it is a statement of loyalty, not a legal step that forces you to surrender a foreign passport. Under US law, you do not have to surrender another citizenship in order to naturalize. From the US side, taking the oath does not force you to formally terminate another nationality. US law does not require you to formally terminate another nationality to naturalize, and the government does not ask for proof that you did.

You can also gain a second citizenship later, for example through marriage or ancestry, without automatically losing your US citizenship. Losing US citizenship generally requires a voluntary, intentional act to give it up. That is why renouncing US citizenship is a deliberate, formal process, not something that happens by accident.

Your other country usually has the final say

This is the part that catches most people off guard, so slow down here. Countries handle it in different ways. Some automatically end their citizenship when a national naturalizes elsewhere, some fully allow dual citizenship, and some allow it only with permission or under specific conditions. So the real question is what your country of origin does, because some countries strip your citizenship the moment you naturalize elsewhere.

Because both legal systems apply to you at once, the practical outcome depends on the specific two countries involved. For a broader overview of how dual status works and how people acquire it, see our companion guide, US dual citizenship.

How you obtain US citizenship (with or without a second one)

Most people reach US citizenship the same way, whether or not they plan to keep another nationality. Keeping dual citizenship generally does not change the US application steps, so you file, you are tested and interviewed, and you take the oath. Most people naturalize after holding a green card and meeting residence, physical-presence, good-moral-character, and civics requirements. The usual path runs through a green card and then naturalization:

1. Become a lawful permanent resident (get a green card), for example through family, employment, or another eligible category.
2. Hold the green card and meet the continuous residence and physical presence requirements.
3. Meet good moral character, English, and civics requirements.
4. File Form N-400, attend the interview and test, and take the oath. You can download Form N-400 from the USCIS website.

If you are weighing the difference between staying a permanent resident and naturalizing, our guide on permanent resident vs citizen explains what citizenship adds. If your path to a green card runs through a US-citizen spouse, see citizenship for marrying a US citizen.

Studying for the naturalization test

There is no single required app. USCIS publishes the official civics study materials, practice questions, and the full list of test items on its website. Official and third-party study aids are built from that material. The most reliable approach is to study directly from the current USCIS materials, because the official question set is what governs your interview. Our overview of the US citizenship test walks through what to expect, and the broader naturalization process page covers the interview itself. Be cautious with unofficial apps that may use outdated questions, and confirm the current format on the USCIS site.

Passports, taxes, and other obligations

Being a dual citizen usually means you may hold two passports, but each country sets its own rules for how you use them. US citizens are generally expected to enter and leave the United States on a US passport, while they may use the other country’s passport for that country. Some countries restrict how their nationals may use a foreign passport, and dual status can carry tax or military-service implications abroad. These rules are country-specific, so confirm the requirements of both countries rather than assuming one set covers everything. US tax questions in particular should go to a qualified tax professional.

How an Ellis Porter attorney helps

Dual citizenship sits at the intersection of two legal systems, and the US half is only part of the picture. An Ellis Porter attorney can explain how US naturalization works in your situation, and how taking the oath does and does not affect your other nationality under US law. We can also help you sequence a clean path from a green card to naturalization. For the steps, see our naturalization process guide. Where your other country’s rules matter, we help you identify the right questions to bring to counsel in that country, so you do not make an irreversible move based on a guess.

This article is general information, not legal advice, and does not create an attorney-client relationship. The right path and timeline depend on the specific facts of your case. Consult a licensed immigration attorney.

Frequently asked questions

Does the United States allow dual citizenship?

Yes. US law permits a person to be a citizen of the United States and another country at the same time, and it does not require naturalizing citizens to prove they have renounced another nationality. The US does not formally encourage dual citizenship as a policy matter, but it does not prohibit it either. Whether you can actually keep the other citizenship depends on the other country’s laws, not on US law.

Do I have to give up my original citizenship to become a US citizen?

US law does not require you to surrender another citizenship in order to naturalize. The naturalization oath includes renouncing foreign allegiances as a statement of loyalty, but that is different from a legal requirement to hand back a foreign passport. Some other countries do automatically strip citizenship when their nationals naturalize elsewhere, so the real question is what your country of origin does. Confirm your country’s rules before assuming you can keep both.

Does the naturalization oath mean I lose my old citizenship?

Not by itself. The oath of allegiance asks new citizens to renounce allegiance to foreign states as a matter of loyalty to the United States. From the US perspective, taking the oath does not force you to formally terminate another nationality. Whether your original country treats naturalizing abroad as an act that ends its citizenship is decided by that country’s law, which varies widely.

How do I become a US citizen if I want to keep dual citizenship?

Most people become US citizens through naturalization after holding a green card and meeting residence, physical-presence, good-moral-character, and civics requirements. Keeping dual citizenship generally does not change the US application steps; you file, are tested and interviewed, and take the oath. The dual-citizenship question turns on your other country’s rules. An attorney can help you understand how both systems interact before you file.

Is there an app or tool to study for the naturalization test?

USCIS publishes official civics study materials, practice questions, and the full list of test items on its website, and there are official and third-party study aids built from that material. The most reliable approach is to study directly from the current USCIS civics materials, because the official question set is what governs the interview. Be cautious with unofficial apps that may use outdated questions. Always confirm the current test format on the USCIS website.

Can dual citizens hold two passports and travel on both?

Often yes, subject to each country’s rules. US citizens are generally expected to enter and leave the United States on a US passport, while they may use the other country’s passport for that country. Some countries restrict how their nationals may use a foreign passport, and rules can affect military service or taxes. Because these obligations vary, a dual citizen should confirm the specific requirements of both countries.