IRS Form 866 (Agreement as to Final Determination of Tax Liability) Fax Numbers
Where and How 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.
Form 866 is not something you download and file on your own. It is drafted during an active IRS Examination or Appeals case, usually as a joint effort between the examiner and the taxpayer or their representative, and it exists for internal IRS use rather than as a public-facing filing. Here's what that means for faxing it:
IRS Form 866 Fax Numbers
Form 866 does not have a single published fax number the way most forms on this site do, because it is never something you fill out and send in cold. It is finalized inside an active IRS Examination or Appeals case, and the examiner or Appeals officer handling that case prepares and submits it.
That said, the IRS's own procedures do allow you to sign and return your copy by fax. Per Internal Revenue Manual 8.13.1.3.5, once you have been in contact with your assigned IRS examiner or Appeals officer and your case file documents that contact and your request to submit your signature by fax, the IRS can accept your signed Form 866 by fax for any amount of tax. There is no general public number to list here, your caseworker gives you the correct one for your case. Fax.Plus can still send your signed agreement to that number from a computer, phone, or email, with a timestamped delivery confirmation for your records.
What Happens When You're Ready to Fax Your Signed Form 866
There's no blank Form 866 to download and fax in on your own schedule, this is a document that gets finalized inside an active IRS Examination or Appeals case. Once you and your caseworker have agreed on the terms and told the IRS you'd like to submit your signature by fax, Fax.Plus lets you sign and send your copy of the agreement straight from a computer, phone, or email to the number they give you, with a timestamped delivery confirmation for your records.
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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.
Who needs to file an IRS Form 866?
- Corporations and large business entities most commonly file Form 866, typically closing out multi-year or complex tax liabilities during an IRS audit or appeal.
- 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.
- Individual taxpayers and small businesses can use this form too, it's just less common than the large corporate cases above since IRS regulations don't restrict Form 866 to any particular type of taxpayer.
Can Form 866 be faxed to the IRS?
Yes, but only within an active case. Once you've been in contact with the IRS examiner or Appeals officer handling your closing agreement and your case file documents that contact and your request to submit by fax, IRS procedure (Internal Revenue Manual 8.13.1.3.5) allows them to accept your signed Form 866 by fax for any amount of tax. There is no general public fax number for Form 866, your caseworker gives you the one to use.
How does a Form 866 closing agreement actually get started?
You don't download Form 866 and file it on your own initiative. It comes out of an active IRS Examination or Appeals case: once you and the IRS reach agreement on your final tax liability for a given period, the examiner or Appeals officer drafts the agreement, often working with you or your representative on the wording, and you sign it before it goes to the IRS for countersignature.
Can the IRS reopen a case after a Form 866 agreement is signed?
Only in narrow circumstances. Once both sides sign, the agreement is final and conclusive for the tax and periods it covers, and the IRS generally cannot reopen or reaudit them. The IRS can still investigate afterward if there's fraud, malfeasance, or misrepresentation of a material fact connected to how the agreement was reached, an honest mistake by the examiner does not qualify.
Is Form 866 only for corporations, or can an individual taxpayer use one too?
Any taxpayer can enter into a Form 866 closing agreement. Corporations and large entities use them most often because their cases tend to involve multiple tax years and complex issues worth locking in permanently, but the underlying authority covers any person, so an individual with a qualifying case can sign one too.
Does a Form 2848 power of attorney matter for a Form 866 agreement?
It can. If you want a CPA, attorney, or enrolled agent to negotiate or sign on your behalf, or simply to be copied on correspondence, the IRS needs a valid Form 2848 power of attorney on file for that person first. Without it, the IRS deals with you directly.
A Form 866 closing agreement usually shows up near the end of a larger IRS case. Here's what else comes up around IRS examinations, appeals, and settling tax matters with the IRS.
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DISCLAIMER: The information on this site is for general information purposes only, and Alohi 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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