Caution: This page (and its links) has not been updated to include all Chapter 4 (FATCA) withholding matters. For Chapter 3 and Chapter 4 withholding obligations, please refer to Publication 515, Withholding of Tax on Nonresident Aliens and Foreign Entities. The publication is available in PDF and HTML (internet) formats. The HTML format includes related topics listed in the hyperlinked table of contents on the left column of the page. Prior year versions of Publication 515 are also available.
You must withhold in accordance with the presumption rules if you know or have reason to know that a Form W-8 or documentary evidence provided by a payee is unreliable or incorrect. If you rely on an agent to obtain documentation, you are considered to know, or have reason to know, the facts that are within the knowledge of your agent.