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ComplianceMarch 28, 2018|UpdatedOctober 15, 2024

What you need to know about Form 6166 (Certification of U.S. Tax Residency)

What is tax residency?

Tax residency refers to the legal tax status of an individual or business entity within a jurisdiction, such as a state or country.

What is Form 6166?

Form 6166, also known as Certification of U.S. Tax Residency, is a letter printed on stationary bearing the U.S. Department of Treasury letterhead that certifies that a person or entity is a United States resident for purposes of the income tax laws of the United States for the fiscal year indicated on the Form.

Companies use Form 6166 to claim income tax treaty and other tax benefits while doing business in foreign countries. Many U.S. tax treaty partners require this proof of U.S. residency from the IRS when a person or business entity is claiming income tax treaty benefits. Form 6166 is also used to claim exemption from a VAT (Value Added Tax) imposed by a foreign country.

What is the process for obtaining Form 6166?

To obtain Form 6166, taxpayers must file Form 8802 (Application for U.S. Residency Certification) with the IRS. Form 8802 is used to request the Form 6166 to show certification of U.S. tax residency.

Only authorized representatives can sign Form 8802. Examples of authorized representatives for a business entity include officers, executives, or duly authorized partners. The IRS also requires specific documentation for particular types of entities.

Request an IRS Form 6166.

Legalization of Form 6166

In order to use Form 6166 in a foreign country, it must first be legalized. Legalization is a process in which various signatures or seals are placed on a legal or public document to verify the origin of the document and the authority of any signatures or seals.

There are two ways in which to accomplish this: Authentication and Apostille. If the country in which your Form 6166 is to be used is NOT a party to the Hague Convention (Hague Convention of 5 October Abolishing the Requirement of Legalization for Foreign Public Documents), then you must Authenticate it. If the country is a party to the Hague Convention, then you can use a more streamlined process known as Apostille. However, every request for an Apostille or Authentication is complicated by the requirements of the destination country’s Consulate. Learn more about Authentications and Apostilles.

Learn more

Foreign government requirements vary greatly and often change without notice. CT Corporation is on top of all Consular rules and requirements, and we learn of any changes quickly. We know each foreign Consulate’s turn-around times and requirements for copies of documents, translations, the intricacies of their application forms, and other nuances.

CT Corporation can manage your Authentications and Apostilles from start to finish

CT Corporation offers a seamless solution to the time-consuming process of Apostille or Authentication.

We will:

  • Advise you on what to prepare down to the last detail to ensure your successful submission
  • Prepare all forms on your behalf
  • Calculate and advance any filing fees, so you only need to cut one check to CT
  • Manage and monitor your requests
  • Deliver and pick up the forms in person
  • Handle bulk orders for multiple forms

CT Corporation can help manage your Authentications and Apostilles for your company’s IRS Form 6166. Contact CT Corporation or order online today.

The CT Corporation staff is comprised of experts offering global, regional, and local expertise on registered agent, incorporation, and legal entity compliance.

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