Tax · United States
IRS Notice CP3219A — Statutory Notice of Deficiency (the 90-day letter)
A CP3219A is a formal determination that the IRS believes more tax is owed. It is not a bill — it opens the one and only pre-payment window to challenge the tax in the U.S. Tax Court, and that window cannot be extended.
How serious: enforcement closeAlso called: CP3219A, 90-day letter, notice of deficiency, Letter 3219, SNOD
The CP3219A is a formal legal determination that the IRS believes you owe more tax. It is usually issued after a CP2000 or CP2501 income mismatch was not resolved.
It is not a bill. It is the notice that opens the one and only pre-payment window to challenge the tax in the U.S. Tax Court, and by law the IRS cannot assess the proposed deficiency until this window closes.
The deadline is absolute: the IRS cannot extend it, and the Tax Court cannot consider a late petition. The last day to file is printed on the notice, which usually arrives by certified or registered mail and includes Form 5564 (Notice of Deficiency – Waiver).
Who sends it
The Internal Revenue Service (IRS) — the United States federal tax authority, part of the Department of the Treasury.
The code 'CP3219A' is printed in the top corner, with the words 'Statutory Notice of Deficiency' and 'Increase in tax'. It usually arrives by certified or registered mail, includes Form 5564 (Notice of Deficiency – Waiver), and prints the last day to file a Tax Court petition.
The deadline
90 days from the notice date to file a petition with the U.S. Tax Court — 150 days if the notice is addressed to you outside the United States; 'This 90-day (or 150-day) period is the time period prescribed by law and cannot be extended by the IRS' (TAS)
There are 90 days from the date printed on the notice to file a petition with the U.S. Tax Court — 150 days if the notice is addressed to a recipient outside the United States. This period is prescribed by law and cannot be extended by the IRS; the last filing day is printed on the notice.
If you do nothing
Without a petition, the IRS assesses the proposed changes and sends a bill. If the deadline is missed, the Tax Court cannot consider the case, and the proposed tax is assessed along with any applicable penalties and interest. The right to challenge the tax before paying it is permanently lost.
Compute your date
The rule above is what the law sets. Put in the dates on your own letter and it becomes a date.
Don't miss this date
We'll email you 7, 3 and 1 day before, and on the day — at 9:00 your time.
We keep only what the reminder needs — type, dates, sender — encrypted. Delete it any time.
How it escalates
- 01After 90 days (150 if addressed abroad), the proposed tax is assessed with penalties and interest, and a bill is sent.
- 02The unpaid bill enters the collection sequence: reminders, a Notice of Federal Tax Lien, CP504 intent to levy the state refund, then the final CDP notice and levy of wages, bank accounts and other property.
- 03The only remaining route to dispute the tax is generally to pay it first and then claim a refund.
How to respond
Response types
- File the objectionPetition to the United States Tax Court · IRC §6213(a)Form: Tax Court Form 2, Petition (or the DAWSON petition generator), with Form 4 Statement of Taxpayer Identification Number and Form 5 Request for Place of Trial; $60 filing fee
- Confirm receiptForm 5564, Notice of Deficiency — Waiver · IRC §6213(d) — waiver of the restrictions on assessment and collectionForm: Form 5564 (enclosed with the notice)
- Ask for clarificationLetter to the IRS with corrected information during the 90-day periodForm: Form 14039, Identity Theft Affidavit, where the deficiency stems from identity theft
- Ask for instalmentsPayment plan for the assessed deficiency · IRC §6159Form: Online Payment Agreement application, or Form 9465, Installment Agreement Request
Where and how
- U.S. Mail (First-Class Mail)
- Certified Mail / Registered Mail (USPS), return receipt requested
- Designated Private Delivery Service (DHL Express / FedEx / UPS — qualifying service levels only)
- DAWSON — the United States Tax Court electronic filing system
- Telephone — the number printed on the notice (general line 800-829-1040)
What makes it count
A petition mailed to the Tax Court is timely if postmarked on or before the last date printed on the notice (IRC §7502), and registered or certified mail is the only way — short of proof of actual delivery — to establish prima facie evidence of timely mailing; a DAWSON e-filing must be received by 11:59 pm Eastern time on that date. Documents sent to the IRS rather than the court go to the address or fax on the notice and follow the ordinary postmark rule, but they never extend the statutory period.
Common questions
Is the CP3219A a bill?
No. It is a formal determination that opens the Tax Court window. By law, the IRS cannot assess the proposed deficiency until that window closes — the bill comes only afterward, if no petition is filed.
Can the 90 days be extended?
No. The period is prescribed by law: the IRS cannot extend it, and the Tax Court cannot consider a late petition. Even sending documents to the IRS during the 90 days does not extend it.
What if the notice was addressed to me outside the United States?
Then the window is 150 days instead of 90. The last filing day is printed on the notice.
What remains if the window is missed?
The proposed tax is assessed with penalties and interest, and a bill is sent. The only remaining route to dispute the tax is generally to pay it first and then claim a refund.
Sources
Facts verified against the sources below on 28 August 2026.