
Section 7701(b) Substantial Presence Test for Foreign Entrepreneurs: The 183-Day Formula, Closer Connection, and Treaty Tie-Breakers
A practical walkthrough of IRC Section 7701(b) for globally mobile founders — the 31-day floor, the weighted three-year 183-day formula, exempt-individual rules, the closer connection exception (Form 8840), and treaty tie-breakers (Form 8833) — with a worked example showing how 130 U.S. days in 2026 can trigger worldwide taxation.










