Form W-8ECI
IRS form for non-residents claiming income effectively connected with US trade or business.
Definition
Form W-8ECI is filed by non-residents whose US-source income is effectively connected with a US trade or business (ECI). ECI is taxed at graduated rates on net basis, not subject to flat 30% FDAP withholding.
Context
Used when a non-resident has ECI; not common for typical disregarded-entity Delaware LLCs without USTB.
Example
A foreign corporation with a US branch generating ECI provides W-8ECI to a payer to avoid FDAP withholding on connected income.
Common pitfalls
- Triggers Form 1040-NR or Form 1120-F filing.
- ECI determination is fact-specific.