Tax
Resident Alien
Also known as: RA, US Resident Alien, Tax-Resident Alien
"Resident alien" is an IRS term of art (26 U.S.C. § 7701(b)) that turns on two alternative tests:
1. Green Card Test — the individual is a lawful permanent resident at any point during the calendar year. Even one day of green-card status during the year makes them a resident alien for that entire year.
2. Substantial Presence Test — the individual was physically present in the US for the requisite number of days under the SPT formula.
Meeting either test makes the individual taxed as a US tax resident: worldwide income, Form 1040 (not Form 1040-NR), all standard deductions, FEIE/FTC eligibility for foreign-source income, and full FBAR/FATCA disclosure obligations on foreign accounts.
Key distinctions vs. the immigration term "resident alien": the IRS definition is purely fiscal. A green-card holder living abroad full-time is still a US resident alien for tax purposes (worldwide-taxation obligation continues). A US-resident H-1B worker who hasn't yet been in the US long enough to meet the SPT is NOT a resident alien for tax purposes — they're a non-resident alien even though they're a lawful US-resident immigration-wise.
Dual-status year. The year an individual transitions from non-resident alien to resident alien (or vice versa) is a dual-status year. Different tax rules apply to the pre- and post-transition halves of the year. Form 1040 plus dual-status statement, or Form 1040-NR for the non-resident portion.
First-Year Choice. Some non-resident aliens can elect to be treated as resident aliens for the year of arrival (Form 1040 + statement attaching to the return). Useful when the standard deduction and filing-jointly options exceed the non-resident-alien tax outcome.
Claiming non-residency despite SPT. The Closer Connection Exception (Form 8840) lets some SPT-meeting individuals claim non-resident-alien status for the year if they had a closer connection to a foreign country and weren't in the US 183+ days during the current year alone.
Sources
Last factual review: 2026-05-08.
Related terms
Non-Resident Alien (NRA)
A Non-Resident Alien (NRA) is a non-US-citizen who meets neither the Green Card Test nor the Substantial Presence Test. NRAs are taxed by the US only on US-source income (typically at flat rates, often 30% gross) and on income effectively connected with a US trade or business (at standard graduated rates). Filed on Form 1040-NR. NRAs are NOT subject to worldwide-income taxation, FBAR, FATCA, or full FEIE/FTC.
Substantial Presence Test (SPT)
The Substantial Presence Test is the IRS's primary test for determining whether a non-US citizen is a US tax resident. It applies a weighted formula: count all days physically present in the US in the current year + 1/3 of days in the prior year + 1/6 of days two years prior. If the total reaches 183, you are a US tax resident — subject to certain exemptions and the closer-connection exception.
Tax Residency
Tax residency determines which country has primary right to tax your worldwide income. Each country sets its own tests — typically based on physical presence (often 183+ days/year), domicile, primary economic interests, or family ties. Holding a residence permit does not automatically establish tax residency, and tax residency does not require a residence permit. Dual tax residency is resolved by tax-treaty tie-breaker rules.
FEIE (Foreign Earned Income Exclusion)
FEIE lets US citizens and resident aliens exclude up to $132,900 (2026) of foreign-earned income from US federal income tax — but not from Social Security/self-employment tax. To qualify, the taxpayer must meet either the Bona Fide Residence Test (full-year tax residence in a foreign country) or the Physical Presence Test (330 full days abroad in any 12-month period). Claimed on IRS Form 2555 attached to Form 1040.