Tax Rules for US Companies Paying Foreign Employees

Tax rules for a US company paying foreign employees hinge on two classification questions that have to be answered before the first payment goes out: is the worker an employee or an independent contractor, and is the worker a US person or a nonresident alien? Those two answers determine which forms you collect, whether you withhold FICA and federal income tax, whether a treaty reduces the rate, and whether the year-end report is a W-2, a 1042-S, or both. Get the classifications right and the rest follows a defined path. Get them wrong and the IRS holds the company personally liable for tax it should have withheld, on top of information-return penalties.

Employee or Independent Contractor

The IRS applies the same common-law test to a worker abroad that it applies to one in the US. The analysis looks at behavioral control (does the company direct how the work gets done), financial control (does the company set how the worker is paid, reimburse expenses, or provide equipment), and the nature of the relationship (is there a written contract, are benefits offered, is the arrangement ongoing).¹

The classification decides which framework you’re in. An employee pulls you into payroll-tax analysis, W-2 reporting, and potential FICA obligations. A contractor pulls you into the 30% statutory withholding regime and Form 1042-S reporting. If the IRS later reclassifies a contractor as an employee, the company owes the employment taxes it should have been withholding, including the employer’s share of Social Security and Medicare, plus interest.¹ IRC Section 3509 sets reduced penalty rates on the unpaid amounts, but those add up quickly at scale.

US Person or Nonresident Alien

The second question isn’t about citizenship alone. A US person includes any US citizen, any lawful permanent resident, and any foreign national who meets the substantial presence test. That test counts days physically present in the US over a three-year rolling period: all days in the current year, one-third of days in the prior year, and one-sixth of days two years back. Hit 183 or more (with at least 31 days in the current year) and the person is a resident alien for tax purposes.²

A nonresident alien is anyone who doesn’t fit those categories.³ US persons are taxed on worldwide income under the same rules as domestic workers. NRAs are taxed only on income sourced within the United States, modified by any applicable treaty.

Forms to Collect Before Paying Anyone

Every foreign worker has to be documented before the first payment. The specific form depends on tax status.

W-9 for US Persons

A worker who is a US person completes Form W-9, providing a Social Security number or employer identification number and certifying US status.⁴ Same form used for domestic workers.

W-8 Series for Nonresident Aliens

An NRA individual signs Form W-8BEN to certify foreign status and, if the country of residence has a US tax treaty, to claim the reduced rate. A foreign entity uses Form W-8BEN-E for the same purposes.⁵

W-8BEN forms expire. A signed form is generally valid from the signature date through the last day of the third following calendar year. A form signed on March 1, 2026, expires on December 31, 2029. It becomes invalid sooner if the worker’s circumstances change, such as moving to the US or becoming a US resident, and the worker must notify the company within 30 days.⁶ If the form expires and payments keep going out, the legal basis for reduced withholding is gone and the full 30% applies.

ITIN When There’s No SSN

Many NRAs have no Social Security number. When US reporting requires a taxpayer identification number, the worker applies for an Individual Taxpayer Identification Number on Form W-7. A passport is the only standalone document that satisfies both identity and foreign-status requirements. Processing typically takes about seven weeks, and nine to eleven weeks during peak season (mid-January through April) or when filing from overseas.⁷

FICA on Employees

Social Security and Medicare rules split on tax status.

US Citizens and Resident Aliens Abroad

FICA generally applies to their wages regardless of where the work is performed. For 2026, the employer’s share is 6.2% for Social Security on wages up to $184,500 and 1.45% for Medicare on all wages, with the employee matching.⁸

The exception is a totalization agreement. The US maintains these bilateral social-security treaties with roughly 30 countries, and they prevent the worker and employer from paying into both systems on the same wages.⁹ To stop US FICA withholding, the employee obtains a Certificate of Coverage from the country whose system will cover them, and the company keeps that certificate in its payroll records.¹⁰ Without a totalization agreement, the company withholds and matches FICA in the ordinary way.

NRA Employees Working Outside the US

Services performed entirely outside the United States by an NRA fall outside the definition of “employment” for FICA. Under IRC Section 3121(b), services performed abroad only count as FICA-taxable employment if the worker is a US citizen or resident alien.¹¹ An NRA working from their home country doesn’t meet that threshold, so no FICA withholding is required.

Federal Income Tax Withholding on Employees

US Citizens and Resident Aliens

Withhold federal income tax on wages paid to US citizens and resident aliens abroad the same way you would for a domestic employee, using Form W-4.¹² These employees may owe little or no US tax because of the foreign earned income exclusion, which for 2026 lets qualifying individuals exclude up to $132,900 of foreign earnings.¹³

A US citizen who expects to qualify can submit Form 673 to the employer so withholding is reduced or eliminated on wages expected to be excluded, rather than overwithheld all year.¹⁴ Only US citizens can use Form 673. Resident aliens go through the standard W-4 process.

NRA Employees

An NRA employee’s wages are subject to US income tax withholding unless a treaty exempts them. Many treaties exempt compensation for personal services if the worker meets residency and compensation thresholds. To claim the exemption, the employee submits Form 8233 identifying the specific treaty article.¹⁵ The employer forwards Form 8233 to the IRS. If the claim stands, the employer withholds at the treaty rate. If no treaty applies or no 8233 is filed, the employer uses the standard tables, with special NRA rules that generally require single filing status.

Paying NRA Contractors

When the worker is a contractor and an NRA, the framework changes. It centers on where the services are performed and whether a treaty lowers the default rate.

Where the Work Is Done

US withholding and reporting only apply to US-source income. For personal services, the source is where the work is physically performed. An NRA contractor doing all the work outside the United States earns foreign-source income, and the company has no US withholding or reporting obligation, provided it holds a valid W-8. If the contractor spends time working inside the US, the portion of the payment attributable to that US-based work becomes US-source, so the company needs a way to track and split time by location.

The 30% Default Rate

For US-source income paid to an NRA contractor, IRC Section 1441 sets a default withholding rate of 30% on the gross payment.¹⁶ It covers compensation, royalties, rents, and most other fixed or determinable income. The contractor can reduce or eliminate it by submitting Form W-8BEN or W-8BEN-E claiming treaty benefits.⁵ Many treaties include a personal-services provision that drops the rate to 0% for residents of the treaty country. The valid W-8 has to be in hand before payment. Without it, the full 30% applies, and the company is personally liable for any tax it failed to withhold.¹⁷

Report on 1042-S, Not 1099

A foreign contractor should generally not receive a Form 1099-NEC. US-source income paid to an NRA is reported on Form 1042-S, even when a treaty brings withholding to zero.¹⁸ The 1042-S identifies the income code, the treaty article, and the tax withheld. Payments that are entirely foreign-source and backed by a valid W-8 require no US tax reporting at all.

Year-End Reporting and Deadlines

W-2 for US Persons Abroad

US citizens and resident aliens working abroad receive a standard Form W-2 showing wages, federal income tax withheld, and FICA withheld. File with the Social Security Administration and furnish copies to the employee by January 31 of the following year.¹⁹

Split Reporting for NRA Employees

An NRA employee can trigger a split. Wages subject to regular income tax withholding (no treaty claim) go on Form W-2. Wages exempt from withholding under a treaty claimed via Form 8233 go on Form 1042-S instead.²⁰ A single NRA employee can receive both for the same year if part of the compensation was treaty-exempt and part wasn’t.

Form 1042 Reconciliation

Any company that files Form 1042-S also files Form 1042, which reconciles totals across all 1042-S forms issued for the year. Both are due by March 15 of the following calendar year.²¹ For 2026 payments, that’s March 15, 2027.

Penalties for Getting It Wrong

Under IRC Section 1461, the company is personally liable for tax it was required to withhold but didn’t.¹⁷ The company pays it out of its own pocket even if the foreign worker has already been paid in full and is no longer reachable.

Separate penalties apply for late or incorrect information returns. Form 1042-S penalties are per-form and scale with how quickly the error is fixed, ranging from $60 per form for corrections within 30 days of the due date to $340 per form for filings not corrected by August 1, with higher penalties and no cap for intentional disregard.²⁰ A “small business” for these purposes has average annual gross receipts of $5 million or less over the three most recent tax years. A company with dozens of foreign workers can build six-figure exposure quickly on missed forms.

Permanent Establishment Risk in the Foreign Country

US tax compliance is only half the picture. Hiring a worker in another country can create a corporate income tax obligation in that country. Most US tax treaties contain a “permanent establishment” concept based on the OECD model. If activities in the foreign country cross certain thresholds, that country can tax the company’s business profits there.

Common triggers include an employee who can negotiate or sign contracts on the company’s behalf, a fixed office or workspace used regularly for the business, and staff performing core (not just support) business functions in the country for an extended period. Preparatory and auxiliary work like market research or internal admin generally doesn’t trigger it. Once a worker starts generating revenue, managing clients, or closing deals, the risk rises. The consequences of an unexpected PE finding include retroactive corporate income tax in the foreign country, local filing obligations, and potential double taxation if the structure isn’t set up for treaty relief.

Employer of Record Arrangements

An Employer of Record is a third party that legally employs the worker in the foreign country on the US company’s behalf. The EOR handles local payroll, tax withholding, statutory benefit contributions, and compliance with local employment law. The US company contracts with the EOR as a service provider, not with the worker as an employee.

The model addresses two problems at once. It removes the direct employment relationship that creates permanent establishment risk, and it offloads the work of navigating foreign payroll systems, mandatory benefits, and labor regulations that vary widely by country.

Currency Conversion

All amounts on US tax forms must be expressed in US dollars.²² When paying in a foreign currency, document the exchange rate used on the date of each payment. This applies to W-2 wages, 1042-S reporting, and any other US filing that includes the compensation amount.

Foreign Labor Law Doesn’t Go Away

Following US tax law doesn’t exempt the company from the employment laws of the country where the worker lives. Many countries impose requirements well beyond US standards. Common obligations that catch US employers off guard include 13th-month salary payments (standard across much of Latin America), end-of-service gratuity requirements (common in the Middle East), statutory severance formulas that can reach months of salary, and mandatory paid leave beyond US norms. Whether a worker is an “employee” under local law is decided by each country’s own standard, which may be broader than the IRS common-law test. A worker treated as a contractor under US rules can be an employee under the foreign country’s rules, pulling in all of those obligations regardless of how clean the IRS filings are.

1
Internal Revenue Service. Independent Contractor (Self-Employed) or Employee?
2
Internal Revenue Service. Publication 519 (2025), US Tax Guide for Aliens
3
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4
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5
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6
Internal Revenue Service. Instructions for Form W-8BEN (10/2021)
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Internal Revenue Service. Instructions for Form W-7
8
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9
Internal Revenue Service. Totalization Agreements
10
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11
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12
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13
Internal Revenue Service. IRS Releases Tax Inflation Adjustments for Tax Year 2026
14
Internal Revenue Service. Form 673 (Rev. August 2019)
15
Internal Revenue Service. Instructions for Form 8233 (Rev. December 2025)
16
Office of the Law Revision Counsel. 26 US Code 1441 – Withholding of Tax on Nonresident Aliens
17
Office of the Law Revision Counsel. 26 US Code 1461 – Liability for Withheld Tax
18
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19
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21
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22
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