Dual citizenship Spain–USA: Can Americans naturalize and keep their passport?

Many people who have chosen to live in a foreign country eventually decide to take on the nationality of their chosen land. This can not only strengthen the emotional feeling of “belonging” to that country but can also offer legal and administrative benefits. The situation regarding the process of naturalization can, however, be extremely confusing: Can I adopt Spanish nationality? Do I have to renounce my American nationality? Or can I have dual citizenship? What kind of costs are involved? What are the risks?

In this article, we take a look at the possibility of dual citizenship for Americans living in Spain.

Spain’s formal stance on dual citizenship: The previous nationality must be renounced

Under Spanish civil law, individuals who become Spanish citizens through naturalization must formally renounce their previous nationality—unless they are citizens of certain countries with bilateral agreements based on historic and cultural ties (e.g., Latin American countries, Andorra, Portugal, Philippines, Equatorial Guinea, and France). The United States is not one of these countries, meaning that the renunciation requirement generally applies to U.S. citizens.

However, a legal loophole does exist, as the formal renunciation of American citizenship is not enforced by the U.S.

The situation is referred to as asymmetric enforcement: Whilst Spain requires renunciation, the U.S. does not automatically revoke a person’s citizenship when they acquire another nationality. U.S. law explicitly allows dual citizenship and generally requires a clear intent to abandon U.S. nationality (e.g., through formal renunciation at a U.S. consulate).

As a result, many Americans who naturalize in Spain officially renounce their U.S. citizenship on the Spanish side—but never notify U.S. authorities. Legally, they retain their U.S. citizenship because the U.S. has not accepted or processed the renunciation. Although the Spanish naturalization process includes a promise or oath to renounce the previous nationality, the U.S. passport remains valid if no formal action is taken before U.S. authorities.

Risks and downsides of the loophole

It is important to point out that this loophole exists as a result of the fact that Spain and the U.S. do not currently have a data-sharing agreement. However, if both countries should start sharing data in the future, it could be possible for Americans with both U.S. and Spanish nationalities to lose citizenship in one or even both of the countries.

Also, it remains uncertain as to whether Spain might eventually enforce renunciations more strictly, potentially revoking naturalized citizenship if U.S. nationality is detected.

In addition, Spain will technically only recognize your Spanish citizenship; as a result, legal matters could become complicated if you have to declare your dual nationality.

Furthermore, should you return to the U.S., your dual nationality could have an influence on security clearance and government jobs: In the U.S., using or holding a foreign passport can jeopardize security clearance—even if you acquired it by birth or inheritance.

Tax and financial implications

Dual citizenship can result in complex reporting and possibly even double taxation, as dual citizens are subject to the tax laws of both countries:

• U.S. worldwide income: American citizens must report and pay tax on worldwide income, regardless of where they reside.
  
  
• Spanish income and assets: Residents of Spain must also report global income and assets.
  
  
• Tax treaty: The U.S.–Spain tax treaty helps avoid double taxation and defines taxation rights.
  
  
• Disclosure requirements: U.S. citizens must file FBAR (foreign bank accounts) and FATCA (foreign assets) forms. Spain has its own asset-reporting rules.

Renunciation – The consequences

If you do decide to formally renounce your U.S. citizenship, you will have to pay a renunciation fee (around $2,350) and you may be subject to an exit tax, which is based on the value of your assets. Although Spain and the U.S. have a tax treaty in place to prevent double taxation, you may, as a former U.S. citizen, still be subject to U.S. taxation on certain types of income. You may also lose access to U.S. Social Security and Medicare, as well as the right to enter the U.S. without a visa.

It is therefore absolutely crucial to seek advice from an experienced professional financial advisor before taking the step of renouncing your American citizenship.

Practical procedures and official sources

Steps towards naturalization in Spain (and renunciation of U.S. citizenship)
According to legal guides, in order to qualify for naturalization, U.S. citizens usually need to reside legally in Spain for 10 years (this may be shorter if certain requirements are fulfilled). They will need to pass language and culture examinations—DELE A2 (Spanish) and CCSE (culture/constitution)—at a cost of approximately €134 + €85. A formal application must be submitted (~€104) and, eventually, loyalty must be sworn to the constitution and the King (this includes renunciation of U.S. citizenship). Once the oath has been sworn, a Spanish passport can be applied for (around €300).

Renunciation at the U.S. consulate
If you wish to formally renounce your U.S. citizenship, you must do this in person at a U.S. embassy or consulate. A non-refundable fee (~$2,350) must be paid, and the processing period can take as long as 6–12 months. As already mentioned, an exit tax may apply depending on assets and tax liabilities. Following renunciation, you will have no right to live/work in the U.S., to vote in the U.S., to claim U.S. Social Security, or to enter the U.S. without a visa.

To summarize this information: Yes, Americans can naturalize in Spain and—through a legal loophole—often keep their U.S. citizenship, as Spain’s renunciation requirement is not enforced by U.S. authorities, and there is no automatic data-sharing. However, this does not mean that it is fully legal or without risk.

Potential advantages include having access to two passports, enjoying the right to live, work, study, and own property in Spain/EU, and being able to maintain U.S. citizenship benefits.

Significant risks include the fact that data-sharing or policy changes could lead to a loss of citizenship. Also, there could be problems with security clearance in the U.S. The situation regarding dual tax and financial reporting is complex. If formal renunciation is executed, this incurs fees, exit tax, and the loss of rights and privileges.

What to do if you are considering naturalization (and renunciation)

Obtain precise, updated advice from both U.S. and Spanish official sources (e.g., Spanish Ministry of Foreign Affairs or consular sites, and U.S. Department of State/IRS). Consult expert immigration and tax lawyers with plenty of experience in U.S.–Spain dual citizenship. If you are considering formal renunciation, prepare for financial, legal, and personal consequences.

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