The IRS mails from large campuses in Kansas City, Ogden, Austin, and Holtsville, so the return address alone tells you little. Every real notice carries a CP or LTR number in the top right corner. Look that number up on irs.gov. The IRS also starts contact by mail, not by a phone demand.
What happened
An envelope came with an IRS return address on it. Maybe it says Kansas City, MO. Maybe it says Ogden, UT or Holtsville, NY. The letter asks for money, or asks for information. You want to know where it came from before you do anything.
What usually applies
The IRS works its mail at several large centers around the country. Kansas City, MO 64999 is one of its own addresses. Ogden, Austin, and Holtsville are on its lists too. So the city on the envelope tells you very little. The notice number tells you much more. Look at the top right corner of the page. A real notice carries a CP number or an LTR number there. Search that number on irs.gov. The page for it says what that notice is about and what it asks for. The IRS also makes first contact by mail. It does not open with a call or a text that demands money right now. A QR code on the page proves nothing by itself. The notice number is the part you can check.
“Department of the Treasury Internal Revenue Service Kansas City, MO 64999-0002”
“Fax your response to the location listed on the top left side of the notice: Andover, MA – 877-477-9485 Atlanta, GA – 877-477-0967 Austin, TX – 877-477-0583 Holtsville, NY – 877-477-9599 Fresno, CA – 877-477-0962 Ogden, UT – 877-477-9640 Philadelphia, PA – 877-477-9602”
“To get details on an IRS notice or letter, search for it by number or topic. You can find the CP or LTR number on the right corner of the letter.”
“We normally contact you the first time by mail delivered by the U.S. Postal Service.”
What to do
- 1
Find the notice number
Look at the top right corner of the letter. A real IRS notice carries a CP or LTR number there.
- 2
Look that number up on irs.gov
Search the number on the IRS notices and letters page. Read what that notice is about.
- 3
Compare it with the letter in your hand
Check the tax year, the amount, and the due date. They should match what the IRS page describes.
- 4
Notice how the contact arrived
The IRS starts by mail. A call, text, or email that demands money right now does not fit that pattern.
- 5
Call the IRS itself if something is off
If the number does not turn up, or the letter looks odd, call the IRS at 800-829-1040 and ask.
Use the phone number on the IRS page for that notice, not a number a caller gives you. The Taxpayer Advocate Service is a free part of the IRS for tax problems that are not getting fixed. Low Income Taxpayer Clinics help for free or for a small fee. If money already left your account, tell your bank and report it at IdentityTheft.gov. Your local 211 line can point you to free tax help.
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Sources
- Internal Revenue Service, Where to file paper tax returns with or without a payment (irs.gov)Retrieved 2026-07-31
- Internal Revenue Service, Understanding your CP3219A notice (irs.gov)Retrieved 2026-07-31
- Internal Revenue Service, Understanding your IRS notice or letter (irs.gov)Retrieved 2026-07-31
- Internal Revenue Service, How to know it's the IRS (irs.gov)Retrieved 2026-07-31
Last reviewed 2026-07-31