How to Spot a Fake IRS Letter: Red Flags and How to Verify

You can spot a fake IRS letter in under a minute by checking a few fixed features of real ones. A genuine notice arrives through the U.S. Postal Service, carries a CP or LTR number in the upper right corner of the first page, names a specific tax year and form, and gives you weeks to respond in flat bureaucratic language.¹ A fake letter usually fails on at least one of those points, and often on several.

The Marks of a Real IRS Letter

Start with the notice number. Every legitimate IRS letter has one printed in the upper right corner of the first page. Computer-generated notices use a CP prefix (CP14, CP2000, CP504). Letters written by an IRS employee use an LTR prefix (LTR 12C).² No number in that corner is itself a red flag.

A real notice also has these features:

It refers to a specific return, such as your 2024 Form 1040, not vaguely to “your taxes.”
It uses your full name and shows at least the last four digits of your Social Security number. Scam letters lean on generic greetings like “Dear Taxpayer.”
The return address in the upper left matches a known IRS service center (Ogden, UT; Kansas City, MO; Austin, TX, and others).³
A clear response deadline appears, typically 30 or 60 days out with a specific date.
A phone number and mailing address for replies appear on the letter itself, usually near the top right.

Some legitimate notices arrive by certified mail. The IRS is required to send certain documents that way, including the statutory notice of deficiency (Letter 3219, the “90-day letter”), which starts a 90-day clock to petition Tax Court.⁴ Certified mail from the IRS is almost always real and almost always time-sensitive. Do not throw it away.

You can confirm any notice number against the IRS “Understanding Your IRS Notice or Letter” page at IRS.gov. If the number on your letter doesn’t match anything listed, that is a strong sign the letter is fake.⁵

Red Flags in a Fake Letter

The single biggest tell is tone. Real IRS notices are dry and procedural. If a letter reads like it was written to panic you into acting within hours, it was. Phrases like “immediate arrest,” “final warning before criminal prosecution,” or “your bank accounts will be frozen today” don’t appear in authentic IRS correspondence.

Other giveaways:

Demands for gift cards, wire transfers, cryptocurrency, or prepaid debit cards. The IRS accepts checks, electronic payments through IRS.gov, and card payments through approved processors. Nothing else.⁶
A QR code embedded in the letter. The U.S. Postal Inspection Service calls this “quishing,” and the codes lead to phishing sites built to steal your information. Never scan a QR code in a letter claiming to be from the IRS.⁷
Requests that you email, text, or call in your Social Security number, bank account, or credit card details. A real IRS letter won’t ask for that.
Misspellings, mismatched fonts, blurry logos, or awkward phrasing. Real notices are standardized and machine-generated.
No notice number in the upper right corner.
A return address that is a P.O. Box in a city not tied to an IRS campus, or no return address at all.

What the IRS Will Never Do

Memorize even a few of these and you become nearly scam-proof. The IRS and its authorized agents will never:

Demand immediate payment without first sending a bill by mail. Collection always starts with a written notice and time to respond.⁸
Require payment by a specific method such as gift cards, prepaid cards, or wire transfer.⁶
Threaten arrest, deportation, or loss of your driver’s or business license over unpaid taxes.
Start contact by email, text, or social media to ask for personal or financial information. The IRS only texts you if you specifically opted in.⁶
Leave pre-recorded voicemails demanding a callback.

Any letter, call, or message that does one of these is a scam. It doesn’t have to hit two or three. One is enough.

The One Legitimate Exception: Private Collection Agencies

There is a narrow situation where a letter about your tax debt comes from someone other than the IRS and is still real. The IRS assigns certain overdue accounts to one of three private collection agencies: CBE Group, Coast Professional, and ConServe.⁹

Here is how to check it. The IRS mails you notice CP40 first, telling you your account has been assigned. Only after that does the private agency send its own initial letter. Both letters include a taxpayer authentication number you use to verify the caller when the agency phones. If a company writes claiming to collect a tax debt and you never received a CP40, don’t respond. Legitimate private collectors also never threaten you or ask for gift cards, just like the IRS itself.⁹

How to Verify Before You Act

If something feels off, do not call the phone number or visit the website printed on the letter. Verify independently.

Check your IRS online account. Log in at IRS.gov and look for a matching notice. The IRS posts many notices directly to your digital account, and you can opt in for paperless delivery of certain ones. Some notices are still legally required to be mailed, so a paperless preference doesn’t cover everything.¹⁰

Look up the notice number. Open the “Understanding Your IRS Notice or Letter” page on IRS.gov and enter the CP or LTR number from the upper right. If it matches, the page explains what the notice means and what to do.⁵

Call the IRS directly. Individual tax questions: 1-800-829-1040. Business tax questions: 1-800-829-4933. Both lines run 7 a.m. to 7 p.m. local time.¹¹ An agent can tell you whether the IRS sent you anything at all.

If You Already Responded to a Fake

Acting fast limits the damage. The IRS recommends these steps.¹²

Stop all contact. Hang up, stop replying, send no more money. If you clicked a link or opened an attachment, run antivirus software on the device.
Go to IdentityTheft.gov. The federal site walks you through fraud alerts, credit freezes, and a personalized recovery plan.
File Form 14039, the Identity Theft Affidavit, if someone used your Social Security number to file a fraudulent return or if the IRS instructs you to. You can submit it online at IRS.gov, by fax to 855-807-5720, or attached to a paper return. Most people don’t need to file one, so check the guidelines first.¹³
Request an Identity Protection PIN through your IRS online account. This six-digit number is reissued each January and blocks anyone from filing a return in your name without it. The program is open to any taxpayer who can verify their identity.¹⁴
Contact your state tax agency. State-level protections vary, and most states have their own reporting process.

One more note on the IP PIN: the IRS will never call, email, or text you asking for it. Anyone who does is a scammer.¹⁴

Reporting the Scam

Reporting helps investigators trace the operation and warn other people.

Phishing emails and texts pretending to be from the IRS: forward them to phishing@irs.gov. Sending the email as an attachment rather than a plain forward preserves data investigators use to trace the sender.¹⁵
Fake IRS letters and phone scams: report to the Treasury Inspector General for Tax Administration at 1-800-366-4484 or tigta.gov.¹⁶
General fraud: file at ReportFraud.ftc.gov.¹⁷

Include the date, how the communication reached you, and any contact details the scammer used.

1
Internal Revenue Service. How to Know It’s the IRS
2
Internal Revenue Service. Understanding Your CP2000 Series Notice
3
Taxpayer Advocate Service. Letter 12C
4
Taxpayer Advocate Service. 90-Day Notice of Deficiency
5
Internal Revenue Service. Understanding Your IRS Notice or Letter
6
Internal Revenue Service. Ways to Tell if the IRS Is Reaching Out or if It’s a Scammer
7
United States Postal Inspection Service. Quishing
8
Internal Revenue Service. Topic No. 201, The Collection Process
9
Internal Revenue Service. Private Debt Collection
10
Internal Revenue Service. Online Account for Individuals – Frequently Asked Questions
11
Internal Revenue Service. Let Us Help You
12
Internal Revenue Service. Identity Theft Guide for Individuals
13
Internal Revenue Service. Identity Theft Affidavit
14
Taxpayer Advocate Service. Get an IP PIN to Protect Yourself From Tax-Related Identity Theft
15
Internal Revenue Service. Report Fake IRS, Treasury or Tax-Related Emails and Messages
16
Office of Inspector General. Report Fraud, Waste, and Abuse
17
Federal Trade Commission. ReportFraud.ftc.gov