US Citizens in Portugal: What You Need to Know About Taxes

Moving to Portugal solves many problems Americans face at home, high cost of living, expensive healthcare, a relentless pace of work. Taxes, unfortunately, are not fully among them. The United States is one of only two countries in the world (the other being Eritrea) that taxes its citizens on worldwide income regardless of where they live. That does not mean you will pay double taxes, but it does mean the complexity goes up considerably.

Here is what you need to understand before, during, and after your move.

The Fundamental Rule: You Still File

As a US citizen, you are required to file a US federal tax return every year, no matter where you live. Moving to Portugal does not change this obligation. Your worldwide income, wages, freelance income, rental income, dividends, capital gains, pensions, is reportable to the IRS.

Filing deadlines for overseas residents:

• April 15: Standard deadline (Form 1040)
• June 15: Automatic extension for citizens living and working abroad
• October 15: Further extension available by filing Form 4868

Note that extensions to file are not extensions to pay. If you owe tax, interest accrues from the April 15 deadline regardless of any extension granted.

How to Avoid Paying Tax Twice

The US tax code provides three main mechanisms to prevent genuine double taxation for Americans abroad:

1. Foreign Earned Income Exclusion (FEIE)

The FEIE allows you to exclude up to $126,500 (2024 figure, indexed annually for inflation) of foreign-earned income from US taxation. To qualify, you must meet either the Bona Fide Residence Test (established resident of a foreign country for a full tax year) or the Physical Presence Test (present in a foreign country for at least 330 days in any 12-month period).

Critical limitation: the FEIE applies only to earned income, wages, self-employment income, freelance fees. It does not apply to passive income such as dividends, rental income, capital gains, or pension distributions. For Americans with significant investment income, the FEIE provides less relief than it might appear.

2. Foreign Tax Credit (FTC)

The FTC provides a dollar-for-dollar credit against your US tax liability for income taxes paid to Portugal. For higher earners, particularly those with substantial passive income, the FTC is often more beneficial than the FEIE. The two cannot generally be combined on the same income. A qualified tax specialist will model both scenarios for your specific situation.

3. The US-Portugal Tax Treaty

The United States and Portugal maintain a bilateral tax treaty that defines which country has primary taxing rights over specific income types. The treaty is particularly relevant for pension income, dividends, and government payments. The treaty does not eliminate all complexity but provides clear rules that, properly applied, prevent genuine double taxation for most situations.

The 183-Day Rule and Portuguese Tax Residency

Spend 183 or more days in Portugal in a calendar year and you become a Portuguese tax resident. Portugal then taxes your worldwide income under its domestic rules, just as the US does. The tax treaty and Foreign Tax Credit prevent you from being fully taxed twice on the same income, but the interplay between two countries' worldwide-income tax systems creates genuine complexity that requires professional navigation.

FBAR: The Foreign Bank Account Report

If you open a Portuguese bank account, which you will need to do, and it holds more than $10,000 at any point, FBAR filing is required. This catches many expats off guard.

FATCA: Form 8938

FATCA (the Foreign Account Tax Compliance Act) requires US persons with significant foreign financial assets to file Form 8938 with their tax return. The reporting thresholds are higher than FBAR:

• $200,000 on the last day of the tax year, or
• $300,000 at any point during the year

FATCA and FBAR are separate requirements with different thresholds and different filing destinations. Both may apply simultaneously. If you have a foreign pension, brokerage account, or other financial assets in Portugal, assess your FATCA obligations carefully.

NHR: What You Missed (and What Replaced It)

NHR Is Closed to New Applicants

Portugal's Non-Habitual Resident (NHR) tax regime, which offered 10 years of preferential tax rates, including a flat 20% rate on certain Portuguese-source income and exemptions on most foreign income, was closed to new applicants as of January 1, 2024. If you registered for NHR before that date, your 10-year status remains intact and you should confirm your eligibility period with a specialist.

IFICI: The Replacement Regime

The IFICI (Incentivo Fiscal à Investigação Científica e Inovação) was introduced in 2024 as NHR's replacement. It targets a narrower set of beneficiaries, specific high-value professions, researchers, highly qualified workers in designated sectors, and certain investors. Eligibility criteria are considerably more restrictive than NHR. If you believe you may qualify, consult a specialist to assess your situation before assuming you are eligible.

Portuguese Income Tax

As a Portuguese tax resident, you will also file a Portuguese tax return (the Declaração de IRS). Portuguese income tax is progressive:

Deductions are available for healthcare expenses, education, housing costs, and other categories. A Portuguese accountant (contabilista) can optimise your Portuguese filing just as a US expat CPA optimises your federal return.

Social Security: The Totalization Agreement

The US and Portugal have a Totalization Agreement in place that prevents double Social Security taxation. In most cases, you will pay into one system, either US Social Security or Portugal's Segurança Social, but not both simultaneously. Which system applies depends on your employment situation (self-employed, employed by a Portuguese company, working remotely for a US employer, etc.). Confirm your Social Security obligations early, the rules differ significantly by work status.

The State Tax Gotcha

Why You Need a Specialist

The interaction of US citizenship-based taxation, Portuguese residency taxation, the bilateral tax treaty, FBAR, FATCA, FEIE, FTC, and potentially state tax obligations creates a genuinely complex filing picture. The cost of getting this wrong, in penalties, back taxes, and interest, far exceeds the cost of professional advice.

We strongly recommend hiring a CPA with expat specialisation who understands both the US and Portuguese systems. Annual filing fees typically run $500–1,500 depending on complexity. Look for CPAs who specifically advertise expat tax services or who are members of organisations like the American Citizens Abroad Tax Advisory Council. Your immigration lawyer may be able to provide referrals to trusted tax professionals.