Form 6166: Filing Form 8802 for a U.S. Tax Residency Certificate

To get a Form 6166 U.S. tax residency certificate, file Form 8802 with the IRS, pay a nonrefundable user fee of $85 for individuals or $185 for entities, and allow at least 45 days for the IRS to review the application and mail the certificate. Form 6166 is a letter printed on U.S. Department of Treasury stationery that certifies you are a U.S. resident for federal income tax purposes, and foreign tax authorities generally require it before they will apply a reduced treaty withholding rate or grant a VAT exemption.

Why You Need It

Most U.S. treaty partners will not grant treaty benefits on their own. Without IRS confirmation of your residency, a foreign payer withholds tax at the country’s full statutory rate. On interest income, for example, that rate is commonly 30%, while the applicable treaty might cut it to 10% or zero.¹ Form 6166 is what unlocks the lower rate.

The certificate can also serve as proof of U.S. tax residency when you claim exemption from a foreign country’s value-added tax. When used for VAT purposes, the IRS only certifies your U.S. federal income tax status; it does not confirm that you meet the foreign country’s other VAT requirements.²

Who Can Be Certified

Eligibility covers almost every category of U.S. taxpayer: citizens, green card holders, resident aliens who meet the substantial presence test, domestic corporations, partnerships, trusts, estates, exempt organizations, employee benefit plans, and government agencies. The IRS will only certify you after confirming you have filed the required federal return for the relevant period. For a current-year request, that means your prior-year return must already be on file — a 2026 request, for instance, depends on your 2025 return being filed.²

Many treaties include a “limitation on benefits” clause that can disqualify certain entity structures from treaty relief even if they otherwise qualify as U.S. residents. Check that your entity type is eligible under the specific treaty before applying.

The Pass-Through Entity Trap

The IRS treats LLCs, S corporations, and partnerships as fiscally transparent. The entity itself cannot be certified as a U.S. resident for treaty purposes; only its owners, partners, or shareholders can. This surprises many applicants and causes frequent errors.

A single-member LLC that has not elected corporate taxation is a disregarded entity. The IRS will not certify the LLC. Instead, the owner puts their own name, address, and TIN on Line 6 of Form 8802. If the LLC has never filed Form 8832, the owner must attach a signed statement under penalties of perjury declaring U.S. residency.³

A multi-member LLC is treated as a partnership. The application must list the name and TIN of every partner or member seeking certification, along with the supporting information each would need if applying individually. Every listed partner must submit a Form 8821 authorizing the requester to access their tax records and provide a separate perjury statement, and a general partner must certify that the entity has filed its required return.³ S corporations follow the same pattern: each shareholder’s name, TIN, Form 8821, and perjury statement, plus a corporate officer’s statement confirming the S election has not changed.

Filling Out Form 8802

Form 8802 is the application; Form 6166 is the certificate the IRS mails you after approving it. Getting the application right the first time matters because the user fee is nonrefundable and errors add weeks of processing time.⁴

Name, Address, and TIN

Enter your name, mailing address, and taxpayer identification number exactly as they appear on your most recently filed federal return. Individuals use their SSN or ITIN; entities use their EIN.³ Even a small mismatch between the application and the IRS database will trigger manual review. Don’t use a nickname or a recently changed legal name that hasn’t yet been updated with the IRS.

Tax Years and Countries

List the specific tax year or years you need certified. Certification is generally annual, but you can request the current year and any number of prior years on one application. Estates, employee benefit plans, and exempt organizations may use a streamlined three-year procedure covering the current year and the following two, though a new Form 8802 is still required each year.⁵

List every foreign country where you’ll present the certificate, and confirm the U.S. has an income tax treaty with each one. Bundling all countries and years onto a single Form 8802 saves money because you only pay one user fee.⁵

Treaty Articles and Income Types

The form asks which treaty articles you’ll rely on. That means identifying the provision covering the income at issue: dividends, interest, royalties, pensions, capital gains, or business profits. Someone seeking a reduced royalty rate from Japan would cite the Royalties article of the U.S.–Japan treaty. Leave this blank and the IRS may issue a generic certificate that the foreign authority can reject as insufficient.

Also indicate whether the certificate needs to accompany a specific foreign tax form, such as France’s Form 5000 or Canada’s NR301. This lets the IRS tailor the certificate to what the foreign administration expects.

Attachments and Signature

Some entities must attach documentation proving their legal status. A domestic partnership includes its partnership agreement and a statement that it is fiscally transparent under U.S. tax law. A trust or estate may need a copy of the trust instrument or letters testamentary. If a representative is filing for you, include a valid Form 2848 Power of Attorney; missing authorization forms are one of the most common causes of delay.⁶

Whoever signs must have legal authority to bind the applicant: individuals sign for themselves (both spouses on a joint request, a parent for a minor child), a corporate officer signs for a corporation, a general partner for a partnership, a fiduciary for a trust or estate, and an authorized officer for an exempt organization or benefit plan. The signature is under penalties of perjury and attests that the applicant is a U.S. resident. Current-year requests filed before the prior-year return is due require additional perjury-statement language covering prior-year residency.³

The User Fee

The IRS charges a flat, nonrefundable fee per Form 8802 submitted, not per Form 6166 certificate issued. That’s why bundling countries and years onto one application matters.

Individuals pay $85 per Form 8802, regardless of how many countries or years the application covers.
Nonindividual applicants — corporations, partnerships, trusts, estates, exempt organizations, and all other entities — pay $185 per Form 8802.
Fiscally transparent entities pay $185 per Form 8802, covering the entity and all listed partners or shareholders.

The fee is not refunded if the IRS denies certification because of unfiled returns or other compliance issues.⁵

How to Submit

You can pay the user fee electronically on Pay.gov or by check or money order. The payment method drives how you submit the rest of the application.

Pay Online, Then Fax

Go to Pay.gov and search for “IRS Certs.” You’ll upload a copy of Form 8802 during payment, but that upload alone does not count as filing — the IRS will not process applications submitted only through Pay.gov.⁷

After paying electronically, you can fax the completed Form 8802 and attachments instead of mailing them. Up to 10 Forms 8802 (with attachments) fit in a single transmission, capped at 100 pages, with a cover sheet showing the total page count. The toll-free U.S. fax number is 877-824-9110; from outside the U.S., use 304-707-9792.⁷

Pay by Check, Then Mail

Mail the payment together with Form 8802 and attachments to:

Internal Revenue Service
US Residency Certification
Philadelphia, PA 19255-0625

For private delivery services such as UPS or FedEx:

Internal Revenue Service
2970 Market Street
BLN# 3-E08.123
Philadelphia, PA 19104-5016

If you pay electronically but choose to mail rather than fax, send the application to Department of the Treasury, Internal Revenue Service, Philadelphia, PA 19255-0625. Use a trackable service so you have proof of the submission date. Sending the package to any other IRS address will cause significant delays.⁵

The New Digital Form for Individuals

Since September 28, 2025, individual applicants can complete Form 8802 through the IRS Digital Adaptive Mobile Forms system, which provides a mobile-friendly interface. It is currently limited to individuals; business entities cannot use it yet. The tool generates the form but does not transmit it electronically, so the completed form still has to be mailed or faxed.⁴

Processing Time

Submit at least 45 days before you need the certificate. The IRS will contact you after 30 days if processing will run longer.⁷ Complex applications — pass-through entities, limitation-on-benefits questions, multiple prior years — take longer in practice. There is no expedited processing, so the only safeguard against a missed foreign deadline is extra lead time.

For status questions, call the International Taxpayer Service Call Center at 267-941-1000 (not toll-free) and choose the U.S. residency option, Monday through Friday, 6 a.m. to 11 p.m. Eastern.⁸ Once approved, the IRS mails Form 6166 to the address on your Form 8802.

Using the Certificate Abroad

Each Form 6166 covers a specific tax year and specific country. A 2025 certificate for Germany cannot be used in France, and it cannot be used for 2026 in Germany. If you have multiple payers in the same country, each withholding agent will usually want its own copy for compliance records.

Some foreign authorities accept Form 6166 as issued. Others require an apostille or an authentication certificate from the U.S. Department of State first. Countries that belong to the 1961 Hague Apostille Convention require an apostille; non-members require an authentication certificate.⁹

The State Department’s Office of Authentications handles both. You submit Form DS-4194 with the original Form 6166 and specify the destination country. The fee is $20 per document, nonrefundable, and mail processing runs about five weeks.¹⁰ Not every country requires this step, so check with the foreign tax authority before paying for authentication you may not need.

Getting Additional Copies

Need another certificate for the same tax period, whether for a new country, a different payer, or to replace a lost original? File a new Form 8802 and check the additional-request box. The full user fee applies again.⁵

If nothing has changed since the original application, you can attach a copy of the original Form 8802 instead of resubmitting supporting documentation and write “See attached copy of the original Form 8802” on the signature line. That shortcut only works within 12 months of the most recently issued Form 6166 for that tax period. If a newly added country requires documentation you didn’t previously submit, include the new documentation and sign the form fresh.

Because each additional request costs another $85 or $185 and restarts the clock, plan ahead: list every country you might need on the first application, and make copies of the certificate as soon as it arrives.

If You’re Denied

The most common reason for denial is unfiled returns. The IRS will not certify residency if your filing record is not current. Fix the compliance issue, refile Form 8802, and pay the fee again.

If you believe you were wrongly denied, or if a foreign treaty partner refused benefits despite a valid Form 6166, you can request U.S. competent authority assistance under Revenue Procedure 2015-40. The IRS then works with the foreign country’s competent authority to resolve the residency question by mutual agreement; the U.S. side does not decide the dispute unilaterally. This route is only available for countries that have an income tax treaty with the United States.⁵

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Internal Revenue Service. Instructions for Form 8802 (10/2024)
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