ITIN resource centre
A United States filing obligation does not depend on living in the country, holding a Green Card, or even having earned anything in the year. Here is who has to file, who is often surprised to find that they do, and why filing is frequently worth it even when it is not required.
Written and reviewed by Mr. Bryan Woods, MBA, IRS Certifying Acceptance Agent
The United States taxes its citizens and lawful permanent residents on their worldwide income, wherever they live and wherever the money is earned. Moving abroad does not end the obligation. Neither does being paid in another currency, by a foreign employer, into a foreign bank account, in a country that taxes you already.
Whether you actually have to file for a given year turns on your gross income, your filing status and your age, measured against that year’s filing threshold — and there are situations that require a return regardless of how little you earned, such as self-employment income above a small floor, or owing certain specific taxes.
Two points catch people out. First, relief such as the foreign earned income exclusion and the foreign tax credit usually removes the double tax — but only if you file to claim it. Second, foreign bank and financial accounts carry their own reporting duties, separate from the tax return, with penalties out of all proportion to the paperwork involved.
If you are not a citizen or Green Card holder, the question is different. You are not taxed on your worldwide income; you are taxed on income that is connected to the United States. Rent from a house in Florida, a share of profits from a U.S. partnership, a gain on selling U.S. real estate, U.S.-source royalties, wages for work performed in the country.
Your first task is to establish which side of the residency line you fall on, because it decides which return you file. Meeting the substantial presence test — broadly 31 days in the current year and 183 days on a weighted three-year count — makes you a resident for tax purposes even without a Green Card, and residents file Form 1040. If you do not meet it, you are a non-resident and file Form 1040-NR.
Either way, the return needs a taxpayer identification number. If you cannot obtain a Social Security number, that number is an ITIN — and it is normally applied for at the same time as the return itself.
Who needs an ITINBeyond the general rules, the tax code names five specific situations in which a return is required. The last three surprise people most, because they attach the duty to somebody acting for another person rather than to the person earning the income.
A non-resident alien carrying on a trade or business in the United States during the year must file, and this holds even if there was no income from it, even if the income is exempt under a treaty, and even if the year made a loss. Filing is how you report the position and preserve deductions and treaty claims, so a quiet year is not a year off.
You have no U.S. trade or business, but you do have U.S.-source income — and the tax withheld at source did not fully cover what is owed. A return is required to pay the balance. The mirror image is worth knowing too: where too much was withheld, the return is the only way to get the excess refunded, which is why many people in this position file voluntarily.
If you act as the agent or representative of a non-resident alien and that role carries responsibility for the return, the obligation is yours to discharge. Property managers, attorneys-in-fact and authorised representatives frequently hold this duty without having thought of it in those terms.
Executors, administrators and trustees of an estate or trust belonging to a non-resident alien file on its behalf. The estate or trust is a taxpayer in its own right, and the fiduciary signs for it — which commonly means obtaining an identification number for an entity, or for beneficiaries abroad, before anything can be filed.
A U.S. resident, or a domestic fiduciary or other person, charged with the care of a non-resident alien or of that person’s property must file the return required of them. This is the catch-all: where somebody in the United States is genuinely in charge of an absent taxpayer’s affairs, the filing duty follows the control.
Abstract categories are hard to place yourself in. These are the concrete cases that walk through our door, and what they usually mean in practice.
| Your situation | What it usually means |
|---|---|
| I own a rental property in the United States and live abroad | A U.S. return reporting the rental income, and an ITIN if you have no Social Security number. Filing is also how you claim depreciation and expenses against the rent, which frequently reduces the tax to nothing — but only when a return is actually filed. |
| I sold a U.S. property and tax was withheld at closing | A return to report the sale and reconcile the withholding. The amount withheld often exceeds the actual tax on the gain, and the return is the only route to the refund. |
| I am a partner or member in a U.S. partnership or LLC | You are generally treated as engaged in a U.S. trade or business through the partnership, so a return is required — even in a loss year. You will need an identification number before the partnership can properly report your share. |
| My spouse is a U.S. citizen and files a return | Filing jointly usually lowers the household’s tax, but requires an identification number for you. This is one of the most common ITIN applications we handle, filed together with the couple’s return. |
| I am a citizen who has lived overseas for years and never filed | The obligation continued the whole time. There are established routes back into compliance, and they work far better approached voluntarily than after the IRS makes contact. Talk to us before you file anything. |
| I am a student or researcher on a visa | A return, or a treaty-based claim, is often required even where a treaty removes the tax. Scholarship and grant income has its own rules, and your institution’s letter is usually part of the paperwork. |
| Nothing was earned this year | Check before assuming. A U.S. trade or business requires a return with no income at all, and a return can be worth filing anyway — to recover withholding, to keep an ITIN from expiring, or to start the clock on the assessment period. |
Two separate penalties run on an unfiled, unpaid return: one for filing late and one for paying late, each charged monthly, with interest accruing on top of the tax and the penalties both. The late-filing penalty is the heavier of the two by a wide margin.
Two things follow from that. Filing on time while you arrange payment is materially cheaper than doing neither. And an extension of time to file is not an extension of time to pay — it moves the filing deadline, not the payment one.
A refund has a deadline too. Claim it within roughly three years of the due date or it is simply gone. We have met people who lost real money to that rule.
Ask us about a late or unfiled yearMr. Bryan Woods is an IRS Certifying Acceptance Agent, so your passport is never sent to the IRS. We touch and hold it only long enough to confirm it is valid and photocopy it — one to two days — then courier it straight back to you. Start the online application, or call and talk it through first — both are free.
Please note. This page is general information about United States federal tax rules, not advice about your own circumstances, and rules change. ITIN INTERNATIONAL TAX SERVICES is a private firm authorised by the Internal Revenue Service as a Certifying Acceptance Agent; we are not a government agency and we are not affiliated with the IRS beyond that authorisation. Form W-7 and its instructions are available free of charge from irs.gov. For advice on your situation, please get in touch.
