Do U.S. Expats in Spain Pay Taxes Twice?

Why This Question Even Comes Up

U.S. citizens are generally subject to U.S. federal income tax on their worldwide income even when they live abroad. Spain separately taxes the worldwide income of individuals who qualify as Spanish tax residents. That overlap can place the same item of income within both countries' tax systems.

If you're a U.S. citizen who has become a Spanish tax resident — for example, because you spend more than 183 days in Spain during the calendar year or because the main base or centre of your economic activities or interests is in Spain — both countries may require the same income to be reported. Double-tax relief then depends on the type and source of the income, the domestic rules of each country and the U.S.-Spain Tax Treaty.

That mechanism exists. It just isn't automatic, and it doesn't work the same way for every type of income — which is exactly where most self-filed returns go wrong.

If you are planning a move from the United States, our US to Spain Tax Guide explains the wider Spanish tax, treaty, Social Security and reporting framework. For other cross-border matters, see our Spanish and international tax services.

What the U.S.-Spain Tax Treaty Actually Protects

The 1990 U.S.-Spain Income Tax Treaty (updated by a protocol that entered into force in November 2019) is designed to prevent double taxation — but Article 1(3), the treaty's "saving clause," lets the United States continue to tax its citizens as if the treaty didn't exist. The real protection against double taxation comes from Article 24, which sets out how each country grants credit for tax paid to the other.

The 2019 protocol also modernized several mechanical rules that matter if you hold U.S. investments while living in Spain: dividend withholding was capped at 5% for substantial shareholders and 15% otherwise, withholding on most cross-border interest and royalty payments was eliminated, and a mandatory arbitration process was added for cases where the two tax authorities can't agree. None of that changes the core double-taxation question, but it does affect how much is withheld at source before any credit is even calculated.

Two Real Scenarios, Two Different Fixes

Article 24 doesn't work the same way for every type of income. Which country reduces your tax bill depends on why that income is taxable in the first place — because of where it's earned, or only because you're a U.S. citizen.

There is no single rule under which one country always “gives way.” The credit mechanism depends on the legal source of the income, the taxpayer's status, the relevant treaty provisions and each country's domestic foreign-tax-credit rules.

The Key Thresholds for 2025-2026

The Reporting Duties People Forget

Income tax is only half the picture. Both countries also require you to report the mere existence of foreign assets — separately from any tax you owe — and the penalties for skipping this step apply even when your income tax bill is zero.

Notice that these two obligations can apply to the exact same bank account or brokerage account — reported once to Washington and once to Madrid, under two entirely different sets of rules and thresholds. Neither filing satisfies the other.

If You're Considering the Beckham Law

The Beckham Law allows qualifying inbound taxpayers to use the Spanish non-resident income tax rules with specific modifications while remaining IRPF taxpayers. For purposes of the regime, employment income obtained during its application is generally deemed Spanish-source and the general base is taxed at 24% up to €600,000 and 47% above that amount. Certain foreign-source passive income may fall outside Spanish taxation under the regime. None of this changes a U.S. citizen's federal filing and worldwide-income obligations.

Two consequences are especially important for a U.S. citizen:

• Foreign-source passive income that Spain does not tax under the regime does not generate Spanish tax available as a U.S. foreign tax credit. U.S.-source dividends, interest or rental income may therefore remain fully within the U.S. tax computation, subject to the ordinary U.S. rules applicable to that income.
• The Spanish tax actually paid on employment income may be lower than under ordinary Spanish IRPF. A lower amount of qualifying Spanish tax can mean a lower U.S. Foreign Tax Credit, so residual U.S. federal income tax may remain depending on the taxpayer's U.S. rate, sourcing, credit limitation and other items.

The regime can still produce a lower combined tax burden in appropriate cases, but the result should be modelled using the taxpayer's actual Spanish and U.S. income profile rather than assuming that the Spanish election eliminates double taxation by itself.

If you are assessing eligibility or the filing deadline, see our Beckham Law application guide.

Do You Pay Into Social Security Twice?

Generally no. The U.S.-Spain Totalization Agreement has been in force since April 1, 1988, and exists specifically to stop the same salary from being subject to both countries' social security contributions at once — while also letting you combine work credits from both systems to qualify for a pension you might otherwise fall short of.

In practice: if you're employed by a Spanish company in Spain, you generally pay only into the Spanish system. If you're self-employed, or temporarily assigned to Spain by a U.S. employer, the agreement lets you request a Certificate of Coverage confirming which single system applies, so you're not paying into both. A separate, modernized agreement between the two countries was signed in April 2023 to update this framework — as of this writing it has not yet entered into force, so the 1988 agreement is still the one that governs your situation today.

Seven Practical Tips

1. File even if you owe nothing. FBAR and Form 8938 penalties are separate from your income tax liability — a $0 tax bill does not excuse a missing information return.
2. Compare the Foreign Tax Credit and the FEIE before choosing. The FTC is limited by income category and U.S. tax attributable to foreign-source income; unused qualifying foreign taxes can generally be carried back one year and forward ten years. The FEIE has different eligibility rules and can affect the treatment of foreign taxes and certain U.S. tax attributes, so the better approach depends on the taxpayer's facts.
3. Track Spanish tax by income "basket." Form 1116 separates general category income (like salary) from passive category income (like dividends and interest) — credits from one basket cannot offset U.S. tax on the other, so lumping them together is one of the most common self-filing mistakes.
4. If you're moving under the Beckham Law, track the election deadline from the correct legal starting date. For the principal taxpayer, the Modelo 149 option is generally due within six months from the start-of-activity date shown in the Spanish Social Security registration or in the documentation allowing continued coverage under the home-country system; where Spanish Social Security registration is not mandatory, the relevant documented start-of-activity date applies.
5. Use the U.S. filing extension deliberately. U.S. citizens abroad get an automatic extension to June 15, and can request a further extension to October 15 — filing later, once your Spanish return is finalized, means you calculate the Foreign Tax Credit from real numbers instead of estimates you'll have to amend.
6. If you're self-employed, request a Certificate of Coverage under the 1988 Totalization Agreement before assuming you owe self-employment tax to both countries.
7. Don't overlook Spanish wealth-tax exposure once you're resident. The state Wealth Tax rules include a €700,000 minimum exemption and up to €300,000 for a qualifying habitual residence, but autonomous-community rules can differ. The Solidarity Tax on Large Fortunes also has its own €3,000,000 zero-rate bracket and interactions with exemptions and Wealth Tax, so exposure should be calculated rather than inferred from a single headline threshold.

Frequently Asked Questions

Written by

Jorge Lacasa Alesón

Managing Partner, Law Cappital · Madrid Bar Association (ICAM) Nº135311 · Ex-Grant Thornton · Ex-Vialto Partners

Jorge founded and directs Law Cappital's tax, immigration and corporate practice, advising U.S., UK and internationally mobile clients on Spanish and cross-border tax. Before Law Cappital, he worked as an international tax lawyer at Grant Thornton and at Vialto Partners, the global mobility tax and immigration firm spun out of PwC.

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This article is for general informational purposes and reflects the rules generally applicable at the time of writing (2025–2026 tax years). It is not individual tax or legal advice, and U.S. and Spanish tax rules change — confirm how they apply to your specific situation before relying on them.