Certification of U.S. Residency for Tax Treaty Purposes
U.S. citizens and U.S. residents sometimes need certification of U.S. residency to claim a tax treaty benefit or a reduction of VAT tax with a foreign country. Such persons should file Form 8802 with the IRS to obtain such certification of residency.
The IRS provides this residency certification on Form 6166, a letter of U.S. residency certification. Form 6166 is a computer-generated letter printed on stationary bearing the U.S. Department of Treasury letterhead.