
Form 6166 U.S. Residency Certification: How Businesses and Individuals Use Form 8802 to Slash Foreign Withholding on Royalties, Dividends, and Service Income
Form 6166 is the IRS-issued certificate of U.S. tax residency that unlocks reduced foreign withholding under bilateral tax treaties. Apply with Form 8802 — $85 for individuals, $185 for entities — and one filing covers unlimited countries and certificates, often saving five or six figures per cross-border contract.










