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A Guide to Obtaining United States Residency Certification (Form 6166)

Overview of Form 6166 and its significance for U.S. residents

Form 6166 is a certificate of residency issued by the Internal Revenue Service (IRS) in the United States. It serves as proof that an individual or entity is a resident of the United States for tax purposes. This form is often required when claiming income tax treaty benefits and certain other tax advantages in foreign countries.


To be eligible for Form 6166, one must meet the IRS requirements, such as being subject to U.S. tax based on residency, citizenship, place of incorporation, or similar factors. Even if an entity is exempt from tax or an individual's income falls below the filing threshold, they may still be considered subject to tax and eligible for the certification.

Benefits of United States Residency Certification

  • Tax treaty benefits. Tax treaties exist between the United States and numerous foreign countries, aiming to prevent double taxation and promote cooperation. By presenting Form 6166, you can access reduced tax rates, exemptions, and credits outlined in these treaties, maximizing your tax efficiency

  • Enhanced Credibility: Form 6166 serves as an official certification from the IRS, lending credibility to your U.S. residency status. It is widely recognized and accepted by foreign tax authorities, financial institutions, and other entities, establishing your legitimacy and facilitating smoother interactions.

  • Streamlined Business Operations: For entities operating globally, United States Residency Certification streamlines various business operations. It enables businesses to comply with tax requirements in foreign countries, establish eligibility for tax exemptions and incentives, and enhance their reputation as reliable partners in international ventures.

The Process of Obtaining United States Residency Certification

  • Gather Required Documentation: Begin by collecting the necessary documentation to support your request for United States Residency Certification. This typically includes copies of your most recent tax returns, identification documents, and any additional materials specific to your situation.

  • Complete Form 8802: Form 8802, also known as the Application for United States Residency Certification, is the official form required to initiate the certification process. Ensure that you fill out the form accurately, providing all the requested information and supporting documentation.

  • Submit the Application: Once you have completed Form 8802, submit it to the IRS for processing. Be mindful of any applicable fees and follow the designated submission methods outlined by the IRS, whether it be mail, fax, or electronic submission.

When to File

Make sure to mail your application at least 45 days before the date you need to submit Form 6166. This allows sufficient time for the IRS to process your request and provide you with the certification you require.

It is important to note that the IRS does not accept early submissions for a current year Form 6166. Any requests with a postmark date prior to December 1 of the preceding year will be returned to the sender.

User Fee

Obtaining Form 6166 requires the payment of a user fee, which covers the processing and issuance of the certification. As of the latest available information, the fee for Form 6166 is $85 per certification. However, it's important to note that the fee amount is subject to change, so it's recommended to confirm the current fee on the official IRS website or through the provided application instructions. The user fee can be paid using various methods, including check, money order, or credit card, following the specific instructions outlined.

CPAs for Expats is here to guide you every step of the way

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