Once you're a Spanish tax resident, Spain taxes your worldwide income, including 401(k) and IRA withdrawals and private pensions — these are generally taxable in Spain. But the US, uniquely, also taxes you as a citizen wherever you live, so you keep filing a US return too. Double tax is relieved through foreign tax credits and the US–Spain treaty rather than by either country giving up its claim. US Social Security and US government-service pensions have special treaty treatment (often taxable primarily in the US). The practical reality for Americans in Spain is dual filing — a Spanish Renta return and a US 1040, plus FBAR/FATCA reporting — coordinated so credits flow correctly and you're not over-taxed. This needs joined-up US and Spanish advice; we handle the Spanish side and coordinate with your US preparer.
Citizenship-Based Taxation
Almost every country taxes people based on where they live. The United States is the major exception: it taxes its citizens and green-card holders on worldwide income regardless of where they reside. This single fact is why an American's tax life in Spain is fundamentally different from a Briton's or a Canadian's. A British retiree who becomes Spanish resident largely stops dealing with HMRC; an American who becomes Spanish resident keeps filing a US return for life, on top of becoming a Spanish taxpayer.
So the American in Spain is, by default, inside two tax systems at the same time: Spain taxing them as a resident on worldwide income, and the US taxing them as a citizen on worldwide income. Without relief that would mean double taxation on the same dollars. The whole architecture of foreign tax credits, the US–Spain treaty and various exclusions exists to make sure that — when handled correctly — you ultimately pay roughly the higher of the two countries' tax on a given item, not the sum of both. But "handled correctly" is doing a lot of work in that sentence: it requires the two returns to be prepared in a coordinated way, which is the central theme of this page.
You don't stop being a US taxpayer
Moving to Spain doesn't end your US filing obligations. As a US citizen you remain liable to file US returns and information reports on worldwide income for life. Spain's residence taxation is layered on top. The job of planning is to make the two systems mesh so you're not taxed twice — not to choose one.
How Each US Source Is Treated
Different US retirement income streams interact with the treaty differently. Broadly:
| US source | Spain (if resident) | Notes |
|---|---|---|
| 401(k) / IRA withdrawals | Generally taxable in Spain | Treated as pension/income in Spain; US also taxes — relieved by credits. Roth treatment needs care. |
| Private / company pension | Generally taxable in Spain | Periodic private pensions taxable in country of residence under the treaty. |
| US Social Security | Special treaty treatment | Often taxable primarily in the US under the treaty's government-payments rules — confirm for your case. |
| US government-service pension | Primarily US-taxed | Federal/state government employment pensions generally remain US-taxable. |
| Annuities & investment income | Taxable in Spain | Spain taxes residents' worldwide investment income; credits relieve US tax. |
The headline for most American retirees with a 401(k)/IRA and some Social Security is that Spain will tax the retirement-account withdrawals as income, while Social Security and any government pension follow special rules. A particular trap is the Roth IRA: it's tax-free on the US side, but Spain doesn't automatically recognise that status, so Roth withdrawals can be taxable in Spain even though they're tax-free to the IRS. That asymmetry can undermine the entire point of a Roth for someone living in Spain, and is exactly the kind of thing that needs checking before you rely on it.
Social Security & Government Pensions
US Social Security and US government-service pensions sit in a different part of the treaty from ordinary pensions. The treaty contains specific rules for government payments and for social security, and the typical result is that these are taxable primarily by the paying country — the US. So a retired American living in Spain on Social Security and, say, a federal pension may find that income remains principally within the US tax net rather than Spain's.
That doesn't mean Spain ignores it entirely — as with other countries, exempt foreign income can still be taken into account when working out the Spanish tax rate on your other income. And the precise treatment depends on the exact nature of the payment and the treaty article that applies, which is genuinely technical. The practical point for planning is that the mix of your US income matters: someone whose retirement income is mostly Social Security and a government pension has a very different Spanish exposure from someone drawing heavily on a 401(k), even with the same total income. Mapping your income sources against the treaty articles is the foundation of getting it right.
Avoiding Double Tax
The mechanism that stops you paying twice is the foreign tax credit, backed by the treaty's relief article. In simple terms, where both countries tax the same income, one country gives credit for the tax paid to the other, so the combined bill is capped at roughly the higher of the two rates rather than the total. Which country gives the credit depends on which has the "primary" taxing right over that income under the treaty — and that's where the source-by-source analysis above feeds in.
For most American retirees in Spain, the practical pattern is: Spain taxes the retirement-account and pension income as the country of residence, the US taxes the same income as the country of citizenship, and credits are claimed so the same dollars aren't taxed twice. Because Spanish rates on pension income can be higher than US rates, the credit often eliminates the additional US tax on that income — but the calculations have to be done carefully and in the right order, and the result varies with your specific income mix, region and the year. The treaty also includes a "saving clause" that preserves the US right to tax its citizens, which is why the credits — rather than simple exemption — are the workhorse here.
Dual Filing in Practice
The lived reality for an American in Spain is two coordinated returns each year:
Spanish Renta return
As a resident you file the Declaración de la Renta (Modelo 100) on worldwide income, including US retirement income that Spain taxes.
US Form 1040
As a citizen you file your US return on worldwide income, claiming foreign tax credits for Spanish tax paid (or vice versa, depending on source).
Coordinate the credits
The two returns must be aligned so credits flow correctly between them — timing and ordering matter because the tax years and payment dates don't perfectly align.
Information reports
Add FBAR and FATCA on the US side and, where relevant, Modelo 720 on the Spanish side — these are reporting, not extra tax, but carry steep penalties if missed.
The key word is coordinated. Filing the two returns in isolation, by preparers who don't talk to each other, is where Americans get over-taxed or fall foul of the credit rules. The mismatch in tax years (Spain and the US both use the calendar year, which helps, but payment timing still differs) and the interaction of the saving clause and credits mean the returns genuinely need to be prepared with each other in mind. We handle the Spanish return and work alongside your US tax preparer so the whole thing fits together.
FBAR, FATCA & Modelo 720
On top of the tax returns, Americans in Spain carry a heavy information-reporting burden — and these are where the truly painful penalties live, because they apply even when no tax is due:
- FBAR (FinCEN 114). US persons with foreign financial accounts over a threshold must report them annually to the US Treasury — and your Spanish bank accounts count.
- FATCA (Form 8938). A further US report of specified foreign financial assets above higher thresholds, filed with your 1040.
- Modelo 720. The Spanish mirror image — residents report foreign (i.e. US and other) assets above thresholds to the Spanish authorities.
So the American retiree in Spain is reporting their Spanish accounts to the US and their US accounts to Spain. None of this is extra tax — it's disclosure — but the penalty regimes for getting it wrong are severe on both sides, which is why reporting compliance is treated as seriously as the tax itself. It's also why many US-Spain banking relationships have friction (some institutions are wary of US-person clients because of FATCA), something to factor into how you hold accounts.
Planning & Common Mistakes
The errors that cost Americans in Spain the most:
- Assuming you can stop filing US returns. Citizenship-based taxation means you can't — moving to Spain adds a filing obligation, it doesn't remove one.
- Relying on Roth IRA tax-free status. Spain may tax Roth withdrawals despite their US tax-free status — verify before you count on it.
- Using uncoordinated preparers. Separate US and Spanish returns that don't reference each other lead to lost credits and over-taxation.
- Misapplying the treaty to Social Security/government pensions. These have special rules — treating them like ordinary pensions gets the answer wrong.
- Forgetting FBAR/FATCA/Modelo 720. The reporting penalties are brutal and apply even with no tax owing — the disclosures are not optional.
- Not planning withdrawals around the move. The timing of large 401(k)/IRA distributions relative to becoming Spanish resident can materially change the tax outcome.
The reassuring counterpoint: with coordinated US-Spanish advice, the system works, and Americans retire very happily in Spain. The credits and treaty genuinely prevent double taxation; the reporting is manageable when it's set up properly. What doesn't work is improvising it or assuming Spain works like the UK does for Brits.
How We Help
We handle the Spanish side of an American retiree's tax life and coordinate with your US preparer so the two fit together. That means confirming your Spanish residence position, mapping your US income sources (401(k), IRA, Social Security, government and private pensions) against the treaty, preparing your Spanish Renta return with foreign tax credits applied correctly, and managing Modelo 720 reporting. We flag the Roth and lump-sum-timing issues before they bite and make sure the credit calculations are coordinated rather than siloed. It's detailed cross-border work, in plain English on a clear quote — see our wider moving from the USA and expat tax guides, and book a consultation to map your position.
Related Guides
Moving to Spain from the USA
The full picture for American movers, including tax.
Moving from the USA →Retiring to Spain from the USA
Beyond tax — visas, healthcare and settling in.
Retiring from the USA →Frequently Asked Questions
Yes. The US taxes its citizens and green-card holders on worldwide income regardless of where they live, so moving to Spain does not end your US filing obligation — you keep filing a US return for life. On top of that, as a Spanish resident you also file a Spanish return on worldwide income. Double taxation is relieved through foreign tax credits and the treaty, not by either country dropping its claim.
Generally yes — once you're a Spanish tax resident, withdrawals from 401(k)s and traditional IRAs are typically taxable in Spain as income. The US also taxes them, but foreign tax credits relieve the double charge so you're not taxed twice. Roth IRAs are a special case: Spain may tax Roth withdrawals even though they're tax-free in the US, so don't assume Roth status carries over.
US Social Security falls under special treaty rules for government/social-security payments and is often taxable primarily in the US rather than Spain. Spain may still take it into account when setting the rate on your other income. The exact treatment depends on the relevant treaty article and your circumstances, so it should be confirmed rather than assumed — it's a common area of error.
Not if it's handled correctly. Where both countries tax the same income, foreign tax credits and the treaty's relief provisions ensure the combined bill is capped at roughly the higher of the two countries' tax, not the sum. Because Spanish rates on pension income can be higher, the credit often eliminates the extra US tax. But the returns must be coordinated and the calculations done in the right order to achieve this.
FBAR (FinCEN Form 114) requires US persons to report foreign financial accounts above a threshold to the US Treasury each year — and your Spanish bank accounts count. There's also FATCA (Form 8938) for specified foreign assets, filed with your 1040. These are information reports, not extra tax, but the penalties for missing them are severe, so they're not optional for Americans living in Spain.
If you're a Spanish resident with foreign (including US) assets above the reporting thresholds, yes — Modelo 720 is the Spanish mirror of FBAR/FATCA, reporting your overseas assets to the Spanish authorities. So Americans in Spain often report their Spanish accounts to the US and their US accounts to Spain. It's disclosure rather than tax, but should be filed correctly to avoid penalties.
Not necessarily. A Roth IRA is tax-free on the US side, but Spain does not automatically recognise that status, so Roth withdrawals can be taxable in Spain. This can undermine the main benefit of a Roth for someone living in Spain. It's exactly the kind of thing to check before relying on it, and may affect decisions about when and where to draw the funds.
Effectively yes, working together. The two returns must be coordinated so credits flow correctly and the treaty is applied properly — uncoordinated preparers are a common cause of over-taxation. We handle the Spanish side and work alongside your US preparer. If you don't have one, getting joined-up US-Spanish advice is one of the most valuable steps an American retiree in Spain can take.