Do expats pay taxes in both countries? Two returns, one real bill

By Skyler Bissell · August 6, 2026 · 8 min read

Berlin taxes a $150,000-equivalent salary at 43.3% all in by our engine's math, roughly ten points above New York's 33.2%, and that gap is the best news in this piece. It is the reason a New Yorker who moves to Berlin usually stops owing the IRS anything at all. The double-taxation fear runs backwards: the more your destination taxes you, the less the US can. What survives the move is paperwork. What rarely survives is a second bill.

Double taxation is the same income taxed in full by two countries in the same year. For US citizens abroad it is almost always prevented by three overlapping mechanisms: the foreign tax credit, the foreign earned income exclusion, and, in narrower cases, a tax treaty. The obligation to file in both countries remains either way.

TL;DR

Most American expats file two returns and pay real tax in one country. Which country collects follows from whose rate is higher. The three shields.
Across most of Western Europe the local bill is the larger one, so the credit zeroes the US bill and banks the surplus for up to 10 future years. The Berlin walkthrough.
The people who do pay twice are predictable: the self-employed outside a totalization agreement, high earners in low-tax destinations, and anyone still domiciled in a sticky US state. The exceptions.

Why Americans abroad file in two countries

The US taxes by citizenship, a design it shares with almost no other country. Move to Germany and the Finanzamt taxes you as a resident on your worldwide income, while the IRS keeps treating you as a taxpayer because of your passport. On paper, both systems claim the same salary. That overlap is where the question comes from, and it is worth taking seriously for one reason: the filing half of it is real. The 1040 keeps arriving every year your income clears the ordinary threshold, whether you owe a dollar or nothing.

Paying is a different matter. Congress built relief mechanisms into domestic law precisely because citizenship-based taxation would otherwise be unworkable, and for a salaried professional in a normal destination they eliminate the second bill entirely. The machinery is worth knowing by name, because which piece does the work depends on where you land.

The calendars are kinder than the folklore, too. Americans abroad get an automatic two-month filing extension to June 15, and a further one to October 15 on request, though interest runs from April 15 on anything owed. Germany, to stay with the example, wants mandatory returns by the end of July of the following year, with employer withholding covering most salaried residents in the meantime. So the overlap is administrative: two calendars, two forms, and for most movers a combined bill identical to what the higher-tax country would have charged on its own.

The three shields, in the order to reach for them

The foreign tax credit (Form 1116). A dollar-for-dollar credit against US tax for foreign income tax paid on the same income, per the IRS. When the foreign bill exceeds the US one, the US liability on that income falls to zero and the unused credit carries back one year and forward ten. This is the workhorse in high-tax destinations, which is most of Europe.
The foreign earned income exclusion (Form 2555). Takes the first $132,900 of 2026 salary earned abroad off the US return altogether, for anyone passing the 330-day physical presence test or the bona fide residence test. It shines where local tax is low, since it needs no foreign tax to work. The qualifying rules and the stacking math get their own guide: the foreign earned income exclusion for 2026.
Tax treaties. The narrowest shield for a salary, and the most misunderstood. Treaties break residency ties, cap withholding on dividends and interest, and sort out pensions, students, and researchers. What they mostly cannot do is shelter a US citizen's paycheck from the IRS, because nearly every US treaty contains a savings clause preserving the right to tax citizens as if the treaty did not exist; the full anatomy is in how do tax treaties work. For wages, the credit and the exclusion do the lifting.

The Berlin walkthrough: how the credit zeroes the US bill

Take the single filer on $150,000 in New York. Our engine puts the full tax bill there at $49,758 a year, an effective 33.2% across federal, state, city, and payroll. The slice the foreign tax credit has to cover is smaller than that: the federal income tax alone, $24,734.

Now move that salary to Berlin. Germany's take at the equivalent gross runs to 43.3% of pay once income tax, the solidarity surcharge, and social insurance are counted. The line that matters for the credit is the income-tax line by itself: €35,829 a year, which converts to about $41,300. Set that against the $24,734 federal bill and the credit clears it entirely, with a five-figure surplus left on the ledger for the following decade. The IRS receives a return showing zero owed, and the return is the whole transaction.

Two boundaries keep the walkthrough honest. Only the income-tax line is creditable; the social-insurance line answers to a different set of rules, the ones totalization agreements exist to referee. And the credit offsets federal tax only, so what a US state thinks of your move is a separate fight entirely.

Who does end up paying twice

The self-employed outside the totalization network. An American freelancer abroad owes 15.3% US self-employment tax on top of local contributions unless a totalization agreement assigns them to one system. Thirty countries hold one with the US; India, Singapore, Israel, and China are among those that do not, and there the double charge is real. The employed version of the trap exists as well: a mover kept on US payroll can have FICA running beside the destination's contributions, the exact scenario the certificate of coverage exists to stop.
High earners in low-tax destinations. Singapore's income tax on a $150,000-equivalent salary is SGD 19,530 by our engine, about $15,300, well under the US federal bill on the same pay. The exclusion shelters its capped slice, the small local tax credits against a bit more, and the IRS taxes the rest. Legal double relief still leaves a real US remainder at high incomes in Singapore, Dubai, and their cousins.
Residents of sticky states. California, Virginia, New Mexico, and South Carolina can keep taxing worldwide income until domicile is formally broken, and no federal credit touches a state bill. The exits are mapped in do expats pay state taxes.
Investment income. The exclusion covers earned income only. Dividends, capital gains, and rental profits ride on the credit alone, and the 3.8% net investment income tax sits outside the credit's reach, so a large portfolio can generate US tax no foreign payment offsets.

Where your destination sits on the rate ladder is the input that decides which shield leads. How countries tax your salary maps the brackets and payroll charges country by country, take-home pay by country ranks 69 of them at three salary points, and the calculator prices your own two cities side by side, taxes included.

FAQ

Do American expats have to file US taxes every year?

Yes, whenever income clears the ordinary filing threshold, which sits near the standard deduction. Owing nothing does not remove the obligation: the return is where the credit and the exclusion are claimed, and skipping it forfeits the paper trail that proves you owe zero.

What happens if my foreign tax is higher than my US tax?

The unused portion of the foreign tax credit does not vanish. Excess credit carries back one year and forward ten, building a ledger you can draw on later, for example against US tax in a year you move home mid-year or receive US-source income while abroad.

Can I use the foreign earned income exclusion and the foreign tax credit together?

Yes, on different slices of income. The exclusion can shelter salary up to its cap while the credit covers tax on income above it. The same dollar of income can never enjoy both, and revoking the exclusion once claimed locks you out of it for five years without IRS consent.

Is a tax treaty required to avoid double taxation?

No. The foreign tax credit is US domestic law and works in every country, treaty or none, which is why Americans in Singapore or Brazil, neither of which has a US income tax treaty, still avoid double income taxation the ordinary way. Treaties matter most for residency tie-breakers, withholding rates, and pensions.

The fear is two full bills. The machinery, in most years and most destinations, produces two returns, one real payment, and a credit ledger quietly working in your favor. Where it breaks is knowable in advance: your state, your employment structure, and your destination's rate, all three checkable before you book the flight.

Sources. Credit and exclusion mechanics: the IRS Foreign Tax Credit and Foreign Earned Income Exclusion pages. City tax bills are computed by cityparity's per-city engine; per-field provenance is in data/_meta.json.

Cross-border tax is fact-specific and rates move; treat the figures as current at publication and put your own situation in front of a professional before relying on them. See the methodology.