Foreign Person: IRS Tax Definition and Classification

Under federal tax law, the IRS definition of a foreign person is anyone who is not a “United States person” as defined in Internal Revenue Code Section 7701(a)(30).¹ The category takes in nonresident alien individuals, foreign corporations, foreign partnerships, foreign trusts, and foreign estates.² The label matters because it triggers a default 30% federal withholding on most U.S.-source income, along with a separate set of certification and reporting rules that don’t apply to domestic taxpayers.

The statute never defines “foreign person” directly. It defines “United States person” and treats everyone else as foreign. A U.S. person is a U.S. citizen, a resident alien, a domestic partnership, a domestic corporation, or certain domestic estates and trusts. If you fall outside all five buckets, you’re foreign.

How the IRS Classifies Individuals

For a human being, the question is residency. An alien (someone who isn’t a U.S. citizen) is a nonresident alien, and therefore a foreign person, unless they pass either the green card test or the substantial presence test during the calendar year.¹

The Green Card Test

If you were a lawful permanent resident of the United States at any point during the calendar year, you pass the green card test and are treated as a U.S. resident for tax purposes. That status continues until the underlying immigration status is officially revoked or administratively determined to have been abandoned. Physically leaving the country doesn’t end it.

The Substantial Presence Test

This test counts days of physical presence over three years. You meet it if you were in the United States for at least 31 days during the current year and at least 183 days during a weighted three-year period.³ The weighted count works this way:

Every day of presence in the current year counts in full.
Each day in the prior year counts as one-third.
Each day two years prior counts as one-sixth.

If the weighted total hits 183 and you spent at least 31 days in the current year, you’re a U.S. resident. Fail both this calculation and the green card test, and you’re a nonresident alien for the year, meaning a foreign person in the IRS’s eyes.³

Exceptions That Preserve Foreign Person Status

Several rules let an individual stay foreign even when the day-count math would otherwise pull them into U.S. residency.

Exempt Individuals

Certain visa holders don’t count their U.S. days toward the substantial presence test at all. Foreign students on F, J, or M visas are generally treated as exempt individuals for their first five calendar years of presence.⁴ Teachers and trainees on J or Q visas are exempt if they haven’t been classified as a teacher, trainee, or student for any part of two of the six preceding calendar years.⁵ Foreign government-related individuals and crew members of foreign vessels also qualify. These exemptions are time-limited; when the year caps expire, the days start counting again.

The Closer Connection Exception

Even if you technically meet the substantial presence test, you can still be treated as a nonresident alien if you keep a closer connection to a foreign country. All four of these conditions must be true: you were present in the United States for fewer than 183 days during the year, you maintained a tax home in a foreign country for the entire year, you had a closer connection to that country than to the United States, and you had not applied for (or had pending) lawful permanent resident status.⁶

The IRS evaluates a “closer connection” by looking at where you keep your permanent home, family, personal belongings, bank accounts, social ties, and driver’s license, along with where you vote and make charitable contributions. To claim the exception, you must file Form 8840 by the due date of your income tax return, including extensions. Miss the deadline and the exception is blocked unless you can show by clear and convincing evidence that you took reasonable steps to comply.⁶

Treaty Tie-Breaker Rules

Some people qualify as U.S. residents under one of the two tests but are also considered residents of another country under that country’s law. When that happens, an income tax treaty between the two countries may contain a tie-breaker rule that decides which country treats the individual as a resident. If the treaty awards residency to the foreign country, the IRS treats the individual as a nonresident alien for purposes of computing U.S. tax liability.⁷ Anyone invoking a tie-breaker files Form 1040-NR with Form 8833 attached to disclose the treaty-based position.

Dual-Status Years

When residency changes mid-year, say a green card arrives in June or a permanent departure happens in September, the calendar year splits in two. During the resident portion, worldwide income is taxable. During the nonresident portion, only U.S.-source income is taxable.⁸

Income earned during the nonresident portion that isn’t connected to a U.S. trade or business faces a flat 30% rate (or a lower treaty rate) with no deductions allowed against it. If you’re a U.S. resident on the last day of the year, you file Form 1040 with “Dual-Status Return” written across the top and attach a statement covering the nonresident period. If you’re a nonresident at year-end, Form 1040-NR takes that role instead, with the same notation.⁸

How Businesses, Trusts, and Estates Get Classified

Corporations and Partnerships

For entities the test is simpler: where was it created or organized? A corporation or partnership formed under the laws of a foreign country is a foreign entity. One formed in the United States or under any state’s laws is domestic.¹ Management location, revenue source, and workforce location are all irrelevant. The jurisdiction of formation is the only factor. Foreign governments and international organizations earning U.S.-source income are also treated as foreign persons on this basis.

Federal regulations list specific entity forms from over 80 countries that are automatically classified as corporations for U.S. tax purposes regardless of internal structure. A foreign entity on that “per se” list cannot elect partnership or disregarded-entity treatment.⁹ Foreign entities not on the list can elect their classification under the check-the-box rules.

Trusts

A trust is foreign unless it satisfies both parts of a two-part test. A domestic trust must meet the court test (a U.S. court can exercise primary supervision over the trust’s administration) and the control test (one or more United States persons control all substantial decisions).¹ Fail either and the trust is foreign. Substantial decisions include distribution timing and amounts, beneficiary selection, termination, investment choices, and litigation decisions; routine bookkeeping doesn’t count.¹⁰ The analysis follows decision-making power, not where the assets sit.

Estates

The statute defines a foreign estate as one whose income from sources outside the United States, to the extent that income isn’t connected to a U.S. trade or business, is not includible in gross income.¹¹ In practice this generally means the estate of a decedent who was not a U.S. citizen or resident at the time of death, since a domestic estate’s worldwide income is generally subject to U.S. tax.

What the Classification Triggers

The 30% Default Withholding

The default withholding rate on U.S.-source income paid to a foreign person is 30%. It applies to fixed or determinable income such as dividends, interest, rent, royalties, and compensation not connected to a U.S. trade or business.¹² The withholding agent, whether a bank, brokerage, employer, or other payer, deducts the tax before releasing the payment.

Effectively Connected Income

Income effectively connected with a U.S. trade or business is treated differently. It generally escapes the flat 30% withholding and is taxed instead at graduated rates after deductions, much like a U.S. person’s income. Partnerships are the main exception: they must withhold on effectively connected income allocated to foreign partners at 37% for non-corporate partners and 21% for corporate partners.¹³

Treaty Rate Reductions

A foreign person living in a country that has an income tax treaty with the United States may qualify for a reduced rate, or a full exemption, on certain income types. To claim the lower rate, the foreign person provides a Form W-8 certifying residence in the treaty country, beneficial ownership of the income, and compliance with any limitation-on-benefits provisions.¹⁴ A withholding agent can’t apply the treaty rate if they know or have reason to know the payee doesn’t actually qualify.

FIRPTA on U.S. Real Estate Sales

When a foreign person sells U.S. real property, the buyer must generally withhold 15% of the total amount realized under the Foreign Investment in Real Property Tax Act.¹⁵ The amount realized includes cash paid, the fair market value of other property transferred, and any liabilities the buyer assumes. This is a prepayment toward the foreign seller’s actual income tax on the gain, not an additional tax.

An exception applies when the buyer is an individual acquiring the property as a personal residence and the sales price is $300,000 or less. The buyer must have definite plans to live in the property for at least half the days it’s used during each of the first two years after the sale.¹⁶ Foreign sellers who believe the 15% exceeds their actual tax liability can apply for reduced withholding by filing Form 8288-B before closing.¹⁷

FATCA Withholding

The Foreign Account Tax Compliance Act adds a separate 30% withholding on certain payments to foreign financial institutions that don’t participate in FATCA reporting and to foreign entities that fail to identify their substantial U.S. owners.¹⁸ When a payment is subject to both Chapter 3 and Chapter 4 withholding, the withholding agent applies Chapter 4 first and doesn’t need to withhold again under Chapter 3 on the same payment. FATCA compliance is generally documented through the W-8 forms.

Certifying Foreign Status with a W-8

Foreign persons receiving U.S.-source income certify their status to the withholding agent on the appropriate W-8. Individuals use Form W-8BEN; entities use Form W-8BEN-E.¹⁹²⁰ These forms go to the withholding agent, not directly to the IRS. The agent keeps them on file to support any reduced withholding.

Each form requires the foreign person’s legal name, country of citizenship or incorporation, a permanent residence address outside the United States, and a taxpayer identification number, which can be U.S.-issued or from the person’s country of residence. Anyone claiming a treaty rate must identify the specific treaty article and the rate being claimed.

Getting an ITIN

Foreign individuals who don’t qualify for a Social Security number can apply for an Individual Taxpayer Identification Number using Form W-7. A valid passport is the only document that can establish both identity and foreign status on its own.²¹ Without a passport, the applicant provides at least two documents from the approved list (such as a national identification card, foreign driver’s license, birth certificate, or U.S. visa), and at least one must include a photograph. Documents must be originals or certified copies, and cannot be expired.

Keeping Documentation Current and Penalties for Getting It Wrong

A W-8BEN or W-8BEN-E generally stays valid from the signature date through the last day of the third succeeding calendar year. A form signed in March 2026, for example, expires on December 31, 2029.²²²³ If anything on the form becomes incorrect, such as a change in country of residence, a new treaty claim, or a shift in entity classification, a new form must be submitted within 30 days.

Withholding agents report payments to foreign persons annually on Form 1042-S, with both the IRS copy and the recipient’s copy due by March 15 of the year following the payment.²⁴ The 1042-S is the foreign person’s equivalent of a W-2 or 1099 for tracking U.S. tax.

Getting the status wrong carries consequences on both sides. A foreign person who provides false information on a W-8 can face penalties for submitting an erroneous, false, or fraudulent certification.²² A withholding agent who fails to withhold the required tax is liable for the full amount that should have been withheld, plus interest and additional penalties, and that liability doesn’t disappear even if the foreign person eventually pays the underlying tax. Agents who help prepare a false certification or fail to disclose knowledge of one face their own civil and criminal exposure, capped at the compensation received from the transaction.²⁵

1
Office of the Law Revision Counsel. 26 USC 7701 – Definitions
2
Internal Revenue Service. Foreign Persons
3
Internal Revenue Service. Substantial Presence Test
4
Internal Revenue Service. Foreign Student Liability for Social Security and Medicare Taxes
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Internal Revenue Service. Exempt Individuals: Teachers and Trainees
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Internal Revenue Service. Closer Connection Exception to the Substantial Presence Test
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Internal Revenue Service. Publication 519 (2025), U.S. Tax Guide for Aliens
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Internal Revenue Service. Taxation of Dual-Status Individuals
9
eCFR. 26 CFR 301.7701-2 – Business Entities; Definitions
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Internal Revenue Service. Treasury Decision 8813 – Residence of Trusts and Estates
11
Legal Information Institute. 26 USC 7701(a)(31) – Foreign Estate or Trust
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Office of the Law Revision Counsel. 26 U.S. Code 1441 – Withholding of Tax on Nonresident Aliens
13
Internal Revenue Service. Withholding on Specific Income
14
Internal Revenue Service. Publication 515 (2026), Withholding of Tax on Nonresident Aliens and Foreign Entities
15
Internal Revenue Service. FIRPTA Withholding
16
Internal Revenue Service. Exceptions from FIRPTA Withholding
17
Internal Revenue Service. About Form 8288-B, Application for Withholding Certificate for Dispositions by Foreign Persons of U.S. Real Property Interests
18
Internal Revenue Service. Withholding and Reporting Obligations
19
Internal Revenue Service. About Form W-8 BEN, Certificate of Foreign Status of Beneficial Owner for United States Tax Withholding and Reporting (Individuals)
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Internal Revenue Service. About Form W-8 BEN-E, Certificate of Status of Beneficial Owner for United States Tax Withholding and Reporting (Entities)
21
Internal Revenue Service. Instructions for Form W-7
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Internal Revenue Service. Instructions for Form W-8BEN
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Internal Revenue Service. Instructions for Form W-8BEN-E
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Internal Revenue Service. Instructions for Form 1042-S
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eCFR. 26 CFR 1.1446(f)-5 – Liability for Failure to Withhold