Dual citizenship — the US position and your home country's

When you naturalize as a U.S. citizen, you will take an oath that includes pledging your allegiance to the United States. But this does not force you to abandon your home country's citizenship—the US accepts dual nationality. The real decision maker, however, is your home country: some nations freely permit dual citizenship while others will strip your citizenship the moment you naturalize abroad. Before you file your naturalization application, you must research and confirm your home country's stance with its embassy or consulate in the United States.

The U.S. Position: The Oath and the Reality

U.S. law does not require naturalizing citizens to give up their home country's citizenship. At the naturalization ceremony, you will recite an oath declaring that you "absolutely and entirely renounce and abjure all allegiance" to any other country. This language has historically confused applicants, but U.S. federal courts and the State Department have consistently clarified that the oath is a statement of loyalty to the United States—not a legal mechanism to strip your foreign citizenship. The U.S. government simply cannot cancel a foreign country's citizenship on your behalf; only that country can decide whether to keep you as a citizen.

USCIS, which administers naturalization through the U.S. Citizenship and Immigration Services, does not ask you to prove you have renounced any foreign citizenship. It does not require you to surrender your foreign passport, nor does it check whether you still hold a second nationality after you take the oath. From the U.S. perspective, you are now a full American citizen entitled to all rights and protections—and if your home country also grants you citizenship, the U.S. law accepts that dual status.

Your Home Country's Rules: The Critical Factor

While the U.S. tolerates dual nationality, your home country may not. Around 75% of countries worldwide now permit some form of dual citizenship, but the remaining 25% do not—and policies vary widely even among those that nominally allow it. Some nations have no restrictions and cheerfully issue passports to dual citizens. Others require you to apply for a 'retention permit' before you naturalize abroad, so you must plan ahead. Still others will automatically terminate your citizenship the moment you complete a U.S. naturalization ceremony, whether you intended it or not.

Three main categories of home-country law exist. First, some countries allow dual citizenship freely and unconditionally—examples include Mexico, Canada, and the United Kingdom. Citizens from these nations can naturalize in the U.S. with confidence that their home citizenship will remain intact. Second, some countries allow dual citizenship under strict conditions; Germany, for example, has historically required a retention permit filed before naturalization. Third, some countries ban dual citizenship outright; if you naturalize in the U.S. while holding their citizenship, they will automatically cancel it on the same day.

Before you file Form N-400 (Application for Naturalization), you must contact your home country's consulate or embassy in the United States and ask directly: will I keep my citizenship if I become a U.S. citizen? Get the answer in writing if possible. Some countries have complex rules that vary by region of origin, prior military service, or family history. Relying on outdated information or online forums can be risky; embassy guidance is definitive.

Passport Rules: Which One to Use and When

As a dual citizen, you now hold two passports, and U.S. law is strict about which one you must use at U.S. borders. Federal law requires all U.S. citizens, including dual nationals, to enter and depart the United States using a valid U.S. passport. You cannot use your foreign passport to enter the U.S., even though you hold it legally. Attempting to do so will cause problems at the border: immigration officers may delay you, question your intent, or deny you entry until you produce your U.S. passport.

This rule applies to all ages, including infants and children who are dual citizens. If you have dual-citizen children, you must obtain U.S. passports for them before any family travel to the U.S., even if your home country issues them passports at birth. U.S. citizens also cannot obtain or use a U.S. visa or ESTA (Electronic System for Travel Authorization); using your foreign passport to apply for an ESTA will result in denial, and the Department of Homeland Security routinely cancels ESTAs belonging to U.S. citizens.

When you travel to your home country, or to other countries, the situation reverses. Your home country may require—or even mandate—that you enter and exit using that country's passport. European Union members, for instance, typically require dual nationals to show their EU passport when crossing EU borders. You should carry both passports when traveling internationally: present your U.S. passport at U.S. immigration and your home-country passport at that country's immigration. Neither choice jeopardizes your citizenship in either country.

U.S. Tax and Reporting Obligations: Citizenship for Life

U.S. citizenship triggers a lifetime tax obligation that no other country's nationality can switch off. The United States taxes its citizens on worldwide income regardless of where they live or how many nationalities they hold. This means if you are a dual citizen living in your home country, working for a foreign employer, and earning income abroad, you still owe U.S. federal income tax on that income. You must file Form 1040 (U.S. Individual Income Tax Return) every year with the IRS, even if you owe no tax or earn no U.S.-source income.

Beyond the basic income tax return, dual citizens holding foreign financial accounts face additional reporting requirements. If the combined value of your foreign bank accounts exceeds $10,000 at any time during the year, you must file an FBAR (FinCEN Form 114—Foreign Bank Account Report). If your foreign financial assets exceed $200,000 (or $50,000 if you are a U.S. resident) at year-end or at any point during the year, you must file Form 8938 with your tax return. These reports are mandatory even if you owe no U.S. tax. Failure to file can result in severe penalties, sometimes exceeding $100,000 per violation.

These rules fall under FATCA (Foreign Account Tax Compliance Act), which requires the IRS and FinCEN to monitor and cross-check foreign financial accounts held by U.S. persons. Foreign banks and financial institutions report account information to the U.S. Treasury, and discrepancies between what you report and what the bank reports trigger IRS audits. Some foreign banks have refused to open or maintain accounts for U.S. dual citizens due to the compliance burden, so the practical impact of U.S. citizenship can affect your ability to bank in your home country.

To reduce the risk of double taxation, the U.S. offers two main relief mechanisms. The Foreign Earned Income Exclusion (FEIE) allows you to exclude the first $132,900 of foreign earned income from U.S. taxation (2026 figure). The Foreign Tax Credit (FTC) allows you to claim a dollar-for-dollar credit for income taxes paid to your home country, reducing your U.S. tax liability. However, these mechanisms do not eliminate all tax complexity, and self-employment taxes often still apply. Many dual citizens living abroad hire tax professionals experienced in expatriate taxation to navigate these rules.

State-level taxes also apply. If you maintain a home or domicile in a particular U.S. state while living abroad as a dual citizen, that state may claim the right to tax your worldwide income. State laws vary significantly, so consult your state's tax authority or a tax professional to understand your obligations. The combination of federal, state, and foreign tax rules can become complex quickly, and filing errors can trigger costly penalties.

Other Dual-Citizenship Considerations

As a dual citizen, you owe allegiance to both countries and must obey the laws of both. This means you are subject to military service obligations in your home country if it requires it, and complying with such a requirement does not endanger your U.S. citizenship. You may also be required to serve in foreign government office or undergo foreign security clearance processes if your home country demands it. While the U.S. will not revoke your citizenship for doing so, these obligations can be time-consuming and may restrict your ability to travel or work.

You are entitled to vote in both countries if both allow it, and you can hold property in both countries. However, you must understand that when you are in your home country using your home-country passport, that country views you as its citizen. If you encounter legal trouble or need consular assistance while abroad, your home country's authorities may treat you as their national first, and the U.S. Embassy may have limited ability to intervene. Additionally, if you travel on your home-country passport, you cannot claim U.S. diplomatic protection in the same way.

Next Steps Before Naturalizing

1. Contact your home country's nearest consulate or embassy in the U.S. and ask in writing whether you will retain citizenship after U.S. naturalization. Request clarification on any conditions, retention permits, or advance filings required.
2. Ask whether your home country requires you to renounce U.S. citizenship or file any notice before naturalizing abroad.
3. Review your home country's passport renewal process and validity period. Plan to renew your home-country passport before it expires, as you will need both passports for international travel.
4. If you have family members who may become dual citizens (spouse, children), confirm their eligibility and any special procedures.
5. Consult a tax professional experienced in expatriate taxation to understand your future U.S. filing obligations and whether your home country taxes worldwide income.
6. Keep records of any official guidance from your home country's consulate. If your home country later claims you lost citizenship, having written documentation of what you were told beforehand is crucial.

If You Decide to Give Up a Citizenship

If you decide you want to hold only U.S. citizenship after naturalizing, you may formally renounce your home country's citizenship. This process is governed entirely by your home country, not by the U.S. Most countries require you to appear in person at a consulate, complete official forms, pay a fee, and receive a certificate of loss of nationality. Some countries impose waiting periods or require proof that you have or will acquire another citizenship to prevent you from becoming stateless. The U.S. will not prevent you from renouncing a foreign citizenship, nor will it require you to. The choice is yours, but it is the foreign country that must process and approve the renunciation.