Dual Citizenship: What U.S. Citizens and Green Card Holders Need to Know

Del Sol CPA
4 days ago
4 min read

Welcome to another article in our series of educational primers on U.S. Tax rules and regulations for expats. The world has grown increasingly interconnected as globalization fosters deeper ties and trade relationships between nations, while international travel and migration have exploded alongside global trade and business. One natural consequence of free travel and trade is an ever-growing number of individuals who can call themselves citizens of more than one country – whether by birth or by choice.

In this breakdown, we’ll focus on the tax implications of dual nationality for U.S. citizens and green card holders; we’ll investigate the practical effects of obtaining or renouncing U.S. citizenship, and we’ll look at what happens during the transition periods between U.S. tax resident statuses.

These are complex topics. People who find themselves in the situations described in this series of articles may also be navigating larger transitions and changes in their lives, and we understand that cross-border tax compliance is often just another thing to worry about on top of a mountain of other concerns. We aim to equip our readers with enough knowledge and context to understand the fundamentals and critical “must-know” aspects of these tax regulations.

When faced with these kinds of challenges, there’s no need to go it alone; Del Sol CPA is here to help. If you find yourself in any of the situations described below, we invite you to connect with one of our expat tax experts for guidance.

Advisory Warning:

All references to dual citizenship and expatriation in this article refer to individuals who are U.S. citizens or green card holders, in addition to one or more other nationalities. If you hold multiple nationalities but are NOT a U.S. citizen or Green Card holder, the information below will not apply to your situation. Any advice and information in this article will be focused on U.S. Tax obligations and likely will not apply to the tax obligations of citizens of other countries.

What is Dual Citizenship? Dual citizenship U.S. tax

As stated by the U.S. State Department, the concept of dual nationality “means that a person is a national of two countries at the same time”. This circumstance may arise in a number of ways; as a simple example, someone born in a non-U.S. country to U.S. citizen parents would inherit U.S. citizenship by descent but may also receive a second nationality from their country of birth.

Is it “legal” to hold multiple nationalities?

The short answer: from a U.S. perspective, yes. From other countries’ perspectives? It depends. An individual may be a U.S. national while also being a national of one or more other countries.

Importantly, U.S. law:

does not impede its citizens’ acquisition of foreign citizenship, whether by birth, descent, naturalization, and
does not require a U.S. citizen to choose between U.S.citizenship and another foreign nationality. Furthermore,
a U.S. citizen may naturalize in a foreign state without any risk to their U.S. Citizenship.

However, many other countries partially or fully ban or restrict their citizens from holding dual citizenship. (For example, China, Japan, the Netherlands). Some countries strip other nationalities automatically, while some, like Japan, have age-based restrictions.

The State Department clearly stipulates that U.S. dual nationals are required to obey the laws of all of their countries of nationality, and any country of which they are nationals has the right to enforce its laws upon them. This principle originates from a 1952 supreme court ruling (Kawakita v. United States), which found that “the concept of dual citizenship recognizes that a person may have and exercise rights of nationality in two countries and be subject to the responsibilities of both”.

Meanwhile, U.S. immigration law does not explicitly address the topic of dual citizenship (although this may change in the future).

What this means for you:

If you are a dual citizen, you are responsible for understanding and adhering to the citizenship laws of all of your countries of nationality. While we can advise you of U.S. regulations, we are not experts on the laws of every country and you may need to conduct your own research to ensure you are in compliance with the laws of each of your countries of nationality.

A few things to keep in mind:

While the U.S. State Department doesn’t prevent or restrict dual nationalities, it does require that U.S. nationals use their U.S. Passport to enter and leave the United States.
A U.S. national, or any child of a U.S. national, is NOT eligible for a U.S. Visa – effectively meaning that if you are a U.S. national, but don’t have a U.S. passport, you will be unable to enter the country until you obtain one.
Perhaps most importantly, all U.S. nationals are obligated to comply with U.S. tax laws.

Did you know?

While many readers of this article are aware that the United States taxes its citizens regardless of their country of residence, fewer may be aware that as of 2026, the US is one of only two countries in the world (the other being Eritrea) that enforces citizenship-based taxation.
If you have a U.S. passport, look inside for a printed message about your tax obligations: “All U.S. citizens working and residing abroad are required to file and report on their worldwide income”.

What Are the Advantages and Disadvantages of Being a U.S. Dual Citizen?

Being a citizen of more than one country can carry significant benefits. Having multiple nationalities often means that an individual enjoys:

Increased travel freedom and flexibility
Access to more social services and benefits
Access to more options for healthcare and education
Significantly enhanced business and trade opportunities
The ability to own property in multiple parts of the world

There can also be downsides, which must be taken into careful consideration – especially for individuals with significant wealth or assets in one or more countries.

Firstly, as previously mentioned, carrying U.S. dual nationality with another country that does not allow multiple citizenship can lead to complex and/or legal implications or legal consequences.

Secondly, and most relevant to the scope of this article, individuals with dual nationality may find themselves subject to taxation in multiple countries!

📚 Article Series: Dual Nationality & U.S. Taxes

U.S. Taxation for Dual Nationals (Coming soon)