Your U.S. Tax Residency Certificate is IRS Form 6166, the residency certification the IRS issues on Treasury letterhead after you file Form 8802. Because it is a federal document, only the U.S. Department of State can apostille it, not a state Secretary of State. Our Washington, DC team reviews your original certificate, completes Form DS-4194, hand-delivers it to the State Department and ships the apostilled certificate anywhere in the world. Expedited service: 9 business days.
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Every Form 6166 is issued by the IRS and can be apostilled only by the U.S. Department of State, wherever you live.
Check that you have the real certificate before you order. Here is an actual Form 6166 issued for the Greece–U.S. tax treaty, with the taxpayer's details redacted.
Sample Form 6166 certifying U.S. residency for the Greece–U.S.A. Double Taxation Convention. Personal details redacted; watermark added by DC Mobile Notary.
“Department of the Treasury, Internal Revenue Service, Philadelphia, PA 19255” across the top, with the IRS Certification Program seal in the corner.
One page on light green-gray paper with a large Treasury and IRS seal printed in the background. A photocopy, scan or PDF cannot be apostilled.
The issue date, taxpayer name, TIN (SSN or EIN) and the tax year being certified.
The certificate names one treaty, for example “for purposes of the Greece – U.S.A. Double Taxation Convention.” Request a separate certificate for each country on Form 8802.
Signed by an IRS Accounts Management official. That signature is what the State Department verifies before it attaches the apostille certificate to your Form 6166. Never remove the attached apostille.
You can't download Form 6166 or fill it out yourself. You request it from the IRS on Form 8802, and the IRS mails the certificate after it confirms your U.S. tax filing status. Here is the process as of November 2026.
The IRS certifies U.S. citizens, resident aliens and U.S. entities that filed the federal return required for the year you need certified, such as Form 1040 for individuals or Form 1120 for corporations. Form 6166 proves residency for treaty or VAT purposes only. It cannot prove that U.S. tax was paid for a foreign tax credit.
List every country and tax year you need on one application, and use line 11 to order more than one original per country. A current-year request needs a penalties-of-perjury statement, and the IRS returns current-year requests postmarked before December 1 of the prior year.
$105 for individuals or $230 for businesses and other entities for applications postmarked on or after October 1, 2026. Pay by check or money order, or online at Pay.gov (search “IRS Certs”) and enter the confirmation number on page 1 of Form 8802. Paying online does not submit your application.
Mail it to the IRS in Philadelphia, or fax it after paying on Pay.gov. Individuals can also file online with the IRS mobile-friendly Form 8802 and an IRS Online Account, available since September 28, 2025; businesses still mail or fax. Current addresses and fax numbers are in the Form 8802 instructions.
The IRS asks you to apply at least 45 days before you need the certificate and contacts you after 30 days if there is a delay. In late October 2026 it reported working on applications received in September 2026.
The IRS mails the original Form 6166 on Treasury letterhead. If the foreign office needs an apostille, send us that original. Don't staple, laminate, write on or notarize it.
Sources: IRS Form 6166, IRS Form 8802 user fees, IRS processing status, U.S. Department of State.
The country where you will use Form 6166 decides which certificate the U.S. Department of State attaches to it.
One step. The State Department apostille is final. Common Form 6166 destinations include France, Germany, Italy, Spain, the United Kingdom, Japan, South Korea, India, China, Brazil, Mexico and Canada. Vietnam joined the Convention on September 11, 2026.
Two steps: a State Department authentication certificate, then legalization by the country's embassy or consulate. Examples include the UAE, Qatar, Kuwait and Egypt. Thailand switches to apostilles on February 28, 2027. Embassy legalization from $495
Before you order: ask the foreign tax office, bank or withholding agent whether they need an apostille, the original certificate only, or a certified translation. Some accept Form 6166 exactly as the IRS issued it.
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No. Send the original Form 6166 exactly as the IRS issued it. The State Department authenticates the IRS official's signature on the certificate itself, so no notarization, copies or added stamps are needed.
No. Form 6166 is a federal document, so only the U.S. Department of State's Office of Authentications can apostille it. A state apostille on a notarized copy certifies only the notary's signature, and foreign tax offices often reject it.
Expedited service takes 9 business days: our DC team hand-delivers your certificate to the State Department. Standard service takes about 3 weeks, and mailing it to the State Department yourself takes 5+ weeks. Getting Form 6166 from the IRS comes first and takes longer, so file Form 8802 early.
No. The State Department authenticates only the original paper certificate printed on Treasury stationery. Tip: on line 11 of Form 8802 you can request more than one original per country, and the user fee stays the same because it is charged per application.
File Form 8802, Application for United States Residency Certification, and pay the IRS user fee. The IRS checks your U.S. tax filing status and mails Form 6166 on Treasury letterhead. Apply at least 45 days before you need it; the full step-by-step guide is above.
For applications postmarked on or after October 1, 2026, the IRS user fee is $105 for individuals and $230 for businesses and other entities (previously $85 and $185). It is one fee per application, no matter how many countries or years you list.
Your Form 6166 gets a State Department authentication certificate, then embassy or consulate legalization, for example for the UAE, Qatar, Kuwait or Egypt. Thailand moves to the apostille system on February 28, 2027. We handle both steps, and embassy legalization starts at $495.
Yes. We complete Form DS-4194, submit your certificate in person, and send status updates and dated submission receipts until your apostilled Form 6166 ships.
Absolutely. Just write “Add Certified Translation” in the message section of your form. We’ll review your document and send you a quote.
We accept credit cards, Zelle, Apple Pay, Google Pay, cash, checks, and other secure online payment options. Final pricing is provided after we review your documents.
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