A non-resident alien for tax purposes is a foreign national who is neither a U.S. citizen nor a resident alien under IRS rules, meaning they fail both the green card test and the substantial presence test for the year. That classification carries real consequences: you owe U.S. tax only on income from U.S. sources, you file Form 1040-NR instead of Form 1040, you generally cannot take the standard deduction, and depending on your visa you may be exempt from Social Security and Medicare tax on your wages.
Resident aliens, by contrast, are taxed the same as U.S. citizens, on worldwide income. So the first thing to settle every year is which category you fall into.
How the IRS Decides Whether You Are a Non-Resident Alien
The IRS runs two tests. Pass either one during the calendar year and you are a resident alien; fail both and you are a non-resident alien.
The Green Card Test
You are a resident alien if you are a lawful permanent resident of the U.S. at any point during the year, meaning you hold a Permanent Resident Card issued by USCIS. Your residency starting date is the first day you are physically present in the country as a green card holder.
The Substantial Presence Test
Even without a green card, enough time on U.S. soil turns you into a resident alien. You meet the test when both are true:
- You were physically present in the U.S. for at least 31 days during the current calendar year.
- Your weighted day count across three years reaches 183 or more, counting all days in the current year, one-third of last year’s days, and one-sixth of the days two years back.
The weighting is what trips people up. Steady travel of roughly four months a year can cross the threshold in year three even though no single year looks heavy.
The Closer Connection Exception
Crossing 183 weighted days does not always end the question. If you were physically present in the U.S. fewer than 183 days in the current year, you can still be treated as a non-resident alien by showing a closer connection to a foreign country. You must meet all four conditions: fewer than 183 days of presence in the current year, a tax home in a foreign country for the entire year, closer ties to that country than to the U.S., and no application or steps toward lawful permanent resident status. The IRS weighs where your permanent home is, where your family lives, where your belongings are, and where you vote, drive, and maintain social ties.
The exception is not automatic. You claim it by filing Form 8840. Skip the form and you lose the benefit, even if the facts clearly favor you.
Exempt Individuals Who Do Not Count Their Days
Some visa holders skip the day count entirely for the substantial presence test. The label “exempt individual” is a bit misleading, since it exempts you from counting days, not from tax. The categories:
- Foreign government employees on A or G visas, other than A-3 and G-5 domestic workers.
- Teachers, researchers, and trainees on J or Q visas who substantially comply with visa terms. J-1 non-students can exclude days for up to two of the last six calendar years.
- Students on F, J, M, or Q visas who substantially comply with visa terms. Students can exclude days for up to five calendar years.
- Professional athletes temporarily in the U.S. to compete in a charitable sports event.
Once the exempt window closes, days start counting. A student who has been in the U.S. on an F-1 visa for more than five calendar years may become a resident alien under the substantial presence test even though the visa has not changed.
How Your Income Gets Taxed
Non-resident aliens owe U.S. tax only on U.S.-source income, and that income splits into two buckets taxed on different rules.
Effectively Connected Income
Effectively connected income (ECI) is money earned through active work or a trade or business in the U.S., including wages, self-employment income for services performed here, and profits from an active U.S. business. ECI is taxed at the same graduated rates that apply to citizens and resident aliens, and you can subtract allowable deductions before the tax is calculated.
FDAP Income
Fixed, determinable, annual, or periodical (FDAP) income is passive U.S.-source income: dividends, interest, rents, royalties, and similar payments. When it is not connected to a U.S. trade or business, FDAP is taxed at a flat 30% of the gross amount, with no deductions permitted. A tax treaty between the U.S. and your home country can lower that rate or eliminate the tax on certain income types, but only if you file the right paperwork ahead of the payment.
Deductions You Can and Cannot Take
Non-resident aliens face tighter deduction rules than residents. The headline restriction is that you generally cannot claim the standard deduction. The one exception is for students and business apprentices from India who qualify under Article 21(2) of the U.S.–India income tax treaty.
For ECI, you can deduct expenses directly connected to earning that income. If you itemize on Schedule A of Form 1040-NR, the available categories are narrower than what a resident can claim, and there is no line for medical expenses. What remains available typically includes:
- State and local income taxes or real property taxes tied to U.S. income.
- Charitable contributions to qualifying U.S. organizations.
- Casualty and theft losses from federally declared disasters, only for the portion above 10% of adjusted gross income and after a $100 per-event floor.
- Gambling losses, only up to gambling winnings, and only if effectively connected with a U.S. trade or business.
For FDAP income that is not effectively connected to a U.S. business, no deductions are permitted at all. The 30% rate applies to the gross figure.
Social Security and Medicare Tax
Certain non-resident aliens are exempt from FICA (Social Security and Medicare) taxes on U.S. wages. The exemption covers individuals in F-1, J-1, M-1, Q-1, and Q-2 status, provided the work is authorized by USCIS and the person remains a non-resident alien for tax purposes.
The exemption has time limits that track the exempt-individual rules. Students hold onto FICA exemption for up to five calendar years. J-1 non-students, including scholars, teachers, and researchers, keep it for up to two calendar years. Once the individual becomes a resident alien under the substantial presence test, the FICA exemption goes away.
Non-resident aliens on H-1B, TN, O-1, or E-3 visas have no FICA exemption; they owe Social Security and Medicare taxes on wages like any other worker. Dependents on F-2, J-2, and M-2 visas do not inherit the exemption.
If an employer withholds FICA in error, ask the employer to refund it first. If that fails, file Form 843 with the IRS, attaching Form 8316 and your W-2.
The Forms You Actually File
Non-resident alien status runs on paperwork that most residents never see.
Form 1040-NR
This is the income tax return for non-resident aliens. You must file it if you engaged in a U.S. trade or business during the year, or if you have U.S.-source income for which the correct tax was not fully covered through withholding. Even when you owe nothing, filing may be necessary to recover overwithholding or to preserve treaty benefits.
Form W-8BEN
You give Form W-8BEN to a withholding agent (a bank, a brokerage, or an employer paying non-wage income) to certify that you are not a U.S. person and, where applicable, to claim a reduced withholding rate under a tax treaty. Without one on file, the payer defaults to 30% withholding on FDAP income.
Form 8233
If a treaty exempts some or all of your compensation from withholding, you file Form 8233 with the withholding agent, typically your employer. It applies to personal services income, and you need a Social Security number or ITIN to use it.
Form W-7 for an ITIN
If you need to file but are not eligible for a Social Security number, apply for an Individual Taxpayer Identification Number using Form W-7. You can submit it with your Form 1040-NR. An ITIN is also required to claim treaty benefits on W-8BEN or 8233.
When Form 1040-NR Is Due
The deadline turns on whether you had U.S. wages subject to income tax withholding:
- If you had wages with withholding, your return is due April 15 of the following year. For tax year 2025, that means April 15, 2026.
- If you did not have wages with withholding, you get an automatic extension to June 15. For tax year 2025, that means June 15, 2026.
Need more time? File Form 4868 by the original due date for an automatic six-month extension to file. It does not extend your time to pay: interest and penalties can still run on any unpaid balance from the original due date.
Treaty Benefits Are Not Automatic
The U.S. has income tax treaties with dozens of countries, and treaties can cut or wipe out U.S. tax on specific income. Common benefits include reduced withholding on dividends and interest, and exemptions for students, teachers, and researchers on scholarships or wages for a limited period.
You have to claim the benefit. For FDAP income, give the withholding agent a completed Form W-8BEN before the payment is made. For personal services compensation, use Form 8233. Report the claimed treaty benefit on your annual Form 1040-NR. Miss the pre-payment paperwork and the payer withholds at the full 30% rate; you then have to file a return to get the excess back.
One trap: not every state recognizes federal treaties. Some states tax non-resident aliens on income that is federally exempt under a treaty, so check the rules of any state where you earn.
What Happens When Your Status Changes Mid-Year
If your status changes during the year, say you arrive as a non-resident and later receive a green card, you have a dual-status year. Which form you use depends on your status on December 31.
- Resident on December 31: File Form 1040 with “Dual-Status Return” written across the top, attaching a Form 1040-NR labeled “Dual-Status Statement” for the non-resident portion.
- Non-resident on December 31: File Form 1040-NR with “Dual-Status Return” across the top, attaching a Form 1040 labeled “Dual-Status Statement” for the resident portion.
During the non-resident portion, only U.S.-source income is taxed. During the resident portion, worldwide income is taxed. The IRS does not currently support attaching the required statement to an e-filed return, so dual-status returns have to be paper-filed.
The Mistake That Costs the Most
The failure-to-file penalty for non-resident aliens is the same as for anyone else: 5% of unpaid tax per month, capped at 25%. For returns due after December 31, 2025, if the return is more than 60 days late, the minimum penalty is $525 or 100% of the unpaid tax, whichever is less. An accuracy-related penalty of 20% of the underpayment applies when negligence or a substantial understatement caused the shortfall.
The bigger problem is often filing the wrong form. A non-resident alien who files Form 1040 instead of Form 1040-NR may claim the standard deduction they were not entitled to, misreport worldwide income, and set off a chain of issues that are hard to unwind. Getting the residency classification right at the start of the year, and re-checking it if your travel or visa situation changes, prevents most of the trouble that follows.