A U.S. business payor making a compensation payment to a non-U.S. independent contractor must withhold an amount sufficient to ensure that at least 30% of the amount subsequently determined to be U.S.-source income is withheld.
U.S. companies can hire non-U.S. citizens as independent contractors without a work visa, provided the contractor performs the work from outside the U.S.
The IRS requires a flat 30% withholding on ALL types of payments to foreign national individuals UNLESS: The individual has a U.S. tax identification number (SSN or ITIN) and qualifies for a tax reduction under the tax treaty between the U.S. and their country of tax residency.
Exemption from withholding To qualify for this exempt status, the employee must have had no tax liability for the previous year and must expect to have no tax liability for the current year. A Form W-4 claiming exemption from withholding is valid for only the calendar year in which it's furnished to the employer.
Payments to a foreign corporation in exchange for personal services performed in the US by either a US citizen or alien is considered to be US-sourced income and is usually subject to withholding. (Can be wages or self-employment income.)
All persons ('withholding agents') making US-source fixed, determinable, annual, or periodical (FDAP) payments to foreign persons generally must report and withhold 30% of the gross US-source FDAP payments, such as dividends, interest, royalties, etc.