🇺🇸 Tax residency in United States

Triggering U.S. tax residency often boils down to more than just how many days you spend stateside. The IRS uses the substantial presence test, a straightforward count of days, but it's not the only game in town. You can actually become a U.S. tax resident without hitting the 183-day mark if your "centre of vital interests" is deemed to be in the United States. Think of it as a more subjective override. This means where your personal ties are strongest,family, social relations, employment, business activities, and even where you keep your bank accounts,can pull you into residency status, even if you're technically below the threshold. It's a backdoor into U.S. tax liability.

Several specific factors can solidify your connection to the U.S. and push you over the edge, even if your physical presence is limited. Owning U.S. real estate, especially if it’s more than just a vacation home you rarely visit, is a big one. Having a spouse or dependents who are U.S. citizens or residents is another significant tie. If you have a registered business operating in the U.S. that you actively manage, that's a strong indicator. Even maintaining a U.S. driver's license or registering to vote (though this is rare for non-citizens) can be used as evidence. These aren't just checkboxes; they paint a picture of where your life is truly centered.

If you do trigger U.S. tax residency, be prepared for worldwide taxation. This means the IRS wants a piece of all your income, no matter where it's earned. For a U.S. resident earning, say, $80,000 globally, after standard deductions, your taxable income might be around $60,000. At the top marginal rate of 37%†, this could mean a federal tax bill of upwards of $22,200, not including state taxes which can add another 5-10% or more depending on your U.S. state of residence. This is a substantial hit, and it's why understanding your residency status is so critical.

There isn't a broad "special regime" for most digital nomads or expats in the U.S. that shelters worldwide income simply by virtue of not being a citizen. However, U.S. citizens are taxed worldwide regardless of where they live, and they must file Form 1040 forever. For non-citizens, if you manage to avoid triggering residency, you're generally only taxed on your U.S.-sourced income. Some individuals might qualify for specific exclusions or credits related to foreign earned income if they meet stringent physical presence tests abroad, but these are complex and don't negate residency status if it's already established.

Interactions with tax treaties can be a lifesaver if you're from a common source country. For U.S. citizens working abroad, the Foreign Earned Income Exclusion (FEIE) and the Foreign Tax Credit (FTC) are the main tools, but they don't eliminate U.S. residency tax obligations if you're physically present in the U.S. long enough. For UK, German, or other treaty country nationals, the treaty might help determine which country has primary taxing rights, often preventing double taxation. For example, a U.S.-UK treaty might stipulate that you're only taxed in the U.S. if your U.S. presence exceeds certain limits or if your permanent home is in the U.S. These treaties are complex, and their application depends heavily on individual circumstances.

Hiring a local U.S. tax accountant who specializes in international or expat tax issues can pay for itself if you have significant foreign assets, complex business structures, or are unsure about your residency status and potential tax liabilities exceeding $10,000†. They can help you properly claim foreign tax credits, navigate treaty provisions, and ensure you're not overpaying or underpaying your U.S. tax obligations.

If you spend more than 31 days in the U.S. in a year, and the sum of your days in the current year and one-third of your days in the previous year, plus one-sixth of your days in the year before that, exceeds 183, you likely trigger the substantial presence test. This information is for educational purposes only and does not constitute legal or tax advice.