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CP400 notice: what it means and what to do
Got an IRS CP400 notice? Here is what it means, your deadline, what to check before you answer, and how to reply. Check your own letter free: it stays on your phone.
Check my CP400 notice freeThis page covers: CP400 notice, CP401 notice.
What the IRS says this notice is about
If you receive a CP400 (individuals) or CP401 (businesses) letter, it explains that your case has been received in Appeals. The letter states that you can expect to be contacted within 45 or 60 days, depending on your type of case.
What letter CP400 and CP401 tells you
- Your case has been received in the Independent Office of Appeals (Appeals)
- Appeals is an independent function within the IRS
- Appeals looks at the facts and the law in your case to try to settle your dispute with the IRS
- You will be contacted within 45 or 60 days, depending on your type of case
- You can call the Appeals Customer Service line to ask about your case if you haven’t heard from Appeals within the timeframe
- A QR code links you to IRS.gov/appeals for more information
Next step
Your assigned Appeals Officer will contact you by letter or phone to schedule the date and time of your appeals conference. To prepare for your appeals conference you may want to view the following:
- Videos of the Appeals process Welcome to IRS Appeals
- Appealing a collection action
- Appealing an examination dispute
Additional information
Publication 5, Your Appeals Rights and How to Prepare a Protest If You Don’t Agree PDF Explains your appeal rights and offers information on how to protest an Internal Revenue Agent's examination report.
Publication 556, Examination of Returns, Appeal Rights and Claims for Refund PDF Explains the general rules and procedures that IRS follows in examinations, what happens during an examination, your appeal rights and how to file a claim for refund of tax you already paid.
Publication 1660, Collection Appeal Rights PDF Explains your appeal rights related to the Collection Due Process & Collection Appeal Program. It also explains collection issues that can be appealed and how to appeal them.
Publication 4167, Appeals - Introduction to Alternative Dispute Resolution PDF Describes the Fast Track Mediation, Fast Track Settlement and Post-Appeals Mediation programs.
Publication 4227, Overview of the Appeals Process Brochure PDF Explains the mission, overview, and expectations of the appeal process to the taxpayer
Your deadline
Answer by the date printed on your notice. If there is no date, answer as soon as you can, and call the number on the notice if you need more time.
What to check before you answer
Send the documents the IRS asks for
Make copies, number the pages, and send them so they arrive by the date on your letter. If you need more time, call before the date and ask for it.
Is this letter really from the IRS?
The IRS writes first by mail. A real letter shows a notice or letter number, your name and part of your tax ID number. The IRS does not ask for payment by gift card, crypto or wire transfer. If in doubt, sign in to your IRS online account, where many notices are listed.
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