IRS Form 866 Fax Numbers: How and Where to Fax a 866 Form?

IRS Form 866 is a formal agreement used primarily by the IRS and large corporations to conclusively settle tax liabilities for specific tax years, helping both parties avoid future disputes over those tax matters.

What is an IRS Form 866?

Form 866 serves as a binding agreement between the Internal Revenue Service and the taxpayer, establishing the final determination of tax liability for a given period. Once signed by both parties, the agreement prevents the IRS from reopening or auditing those years unless fraud, malfeasance, or misrepresentation is discovered.

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Form 866 is not filed directly by the general public, and it's usually used in coordination with IRS Examination or Appeals officers. However, for related correspondence (like when submitting documentation tied to large case resolutions), the IRS provides fax numbers based on location. Below is a general IRS fax reference for Examination offices and LB&I (Large Business & International), which would typically handle Form 866:

IRS Form 866 Fax Numbers

Form 866 is a closing agreement form typically prepared during IRS examinations or appeals. It is not submitted by taxpayers via a standard fax filing by state or region. These agreements are handled directly with IRS personnel, so no central fax number applies for general submissions of Form 866.

How to Submit an IRS Form by Fax?

When it comes to requesting certain tax forms and documents from the Internal Revenue Service agency, you can order such documents from the IRS through fax by getting a local fax number (or port your currently existing fax number) and add the ability to receive faxes in Fax.Plus. All your submitted documents will be accessible for future references in your fully encrypted Faxes tab.

How to fax tax forms online from computer?

Go to the Send Fax section in your Fax.Plus Dashboard, and type in the fax number of your recipient.

Attach your fax document(s) and, if you like, include a cover page.

Click on Send to fax instantly and get an email confirmation of successful delivery.

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Fax tax from your mobile?

Download and install the Fax.Plus app on your smartphone.

Navigate to the Send Fax section and type in the recipient's fax number.

Attach the documents you wish to fax and, if you'd like, include a cover page.

Click on Send to fax instantly and receive the delivery status via push notification.

How to send a fax to the IRS with Gmail, Outlook or Yahoo?

Ensure you're using the email address registered with Fax.Plus.

Compose an email and enter the recipient’s fax number in the To field*.

Attach the documents you want to fax.

Click on Send to fax immediately and get an email confirmation of successful delivery.

* Write the destination’s fax number (along with the country and area code) followed by @fax.plus (example: +16692001010@fax.plus).

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How to Scan and Fax Documents from Phone?

By using Fax.Plus on your smartphone, your device effectively becomes a portable fax machine. Learn how to scan documents by scanning physical documents directly with your camera, then faxing them instantly—no extra steps required.

Download and install Fax.Plus app from the Play Store or App Store.

Launch the app and go to the Send Fax section on the Dashboard.

Tap Add File and choose Scan with Camera to start scanning.
‍Note: You may need to grant permission to access the camera.

Scan the document, make necessary edits such as cropping or enhancing the image, and tap Next.

Enter the recipient's fax number and tap Send.

Who needs to file an IRS Form 866?

Corporations or large business entities undergoing IRS audits or seeking to finalize their tax liabilities.
Taxpayers and their authorized representatives who reach an agreement with the IRS concerning tax due for a specific year or issue.
IRS field agents may also initiate Form 866 when closing cases to document a conclusive agreement.
This form is not used by individuals or small businesses under normal circumstances.

Why do you need an IRS Form 866?

To lock in a final tax liability for a specific tax period, preventing the IRS from reopening the case in the future.
To provide certainty and closure after lengthy audits or appeals.
To protect against future adjustments unless fraud or substantial error is uncovered.
To formalize an agreement reached with the IRS in a legally binding way.

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DISCLAIMER: The information on this site is for general information purposes only, and Fax.Plus cannot guarantee that all the information on this site is current or accurate. This is not intended to be legal, accounting or tax advice and should not be a substitute for professional legal, accounting or tax advice. For legal advice, consult a licensed attorney regarding your specific legal questions.

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