Why verifying an IRS letter matters

Receiving a letter that appears to be from the IRS is stressful. A genuine notice may require a time‑sensitive response; a fake one can be a phishing or extortion attempt designed to steal money or personal data. Verifying authenticity protects you from financial loss, identity theft, and unnecessary legal exposure.

My experience as a CPA working with individuals and small businesses shows that careful verification catches most frauds and prevents costly mistakes. The guidance below combines IRS recommendations with practical steps I use with clients.

How IRS mail typically looks and how it has changed

The IRS has mailed official notices since the agency was established in 1862, and it has modernized many services online. However, the IRS still sends paper letters for many issues—balance-due notices, identity verification requests, CP/Notice and Letter series communications. The IRS also posts information about each notice type so taxpayers can compare details (see IRS, “About IRS Notices”) [https://www.irs.gov/forms-pubs/about-irs-notices].

Key points about format:

  • Genuine IRS letters include a notice or letter number (often at the top right) and a specific tax year.
  • They typically show the last four digits of your SSN or your business EIN—not the full number.
  • Most official IRS correspondence instructs you how to respond and gives a phone number you can use to verify the notice.

Common IRS notice types (brief) and why they matter

  • CP2000: Proposed changes due to underreported income. Respond to agree or provide documentation. (See IRS CP2000 guidance.)
  • CP14/CP501: Notices about balance due. These require quick attention to avoid penalties.
  • Letter 5071C: Identity verification letter asking the taxpayer to verify identity online or by phone.
  • Notice of Deficiency (90-day letter): A formal notice that starts the timeframe for petitioning Tax Court.

(For official descriptions, confirm on the IRS site: https://www.irs.gov/forms-pubs/about-irs-notices.)

Step-by-step verification checklist

Follow these steps before you act on any IRS letter or notice:

  1. Pause and don’t panic.
  • Scammers rely on urgency. Take a breath and plan verification before providing money or personal information.
  1. Inspect the physical letter.
  • Check the notice or letter number (e.g., CP2000, Letter 5071C) and the tax year referenced.
  • Look for the IRS logo, but don’t rely on it—logos can be copied. Verify text details instead.
  • Confirm the return address. While the IRS uses a range of return addresses, a quick cross‑check with IRS contact pages helps.
  1. Compare with the IRS website.
  • Search the IRS pages for the notice/letter name and number. The IRS explains why it sends each notice and what to do next (IRS, “About IRS Notices”).
  • Use your IRS Online Account to check for messages and notices the IRS has posted about your account: https://www.irs.gov/payments/view-your-tax-account.
  1. Do not trust phone numbers or web links printed on suspicious mail.
  • Scammers include fake phone numbers and URLs. If a printed number looks odd or the web address is not an irs.gov domain, treat it with suspicion. The IRS will never initiate contact asking for payment by gift cards, preloaded debit cards, or cryptocurrency (IRS, Impersonation Scams guidance: https://www.irs.gov/newsroom/tax-scams-consumer-alerts).
  1. Call the IRS using a known official number if you still have doubts.
  • For individuals, call IRS customer service at 1-800-829-1040. For businesses, 1-800-829-4933. If you call, have the notice in front of you and confirm the notice number with the agent. (Confirm these numbers on the IRS website before dialing.)
  1. Use the IRS online tools.
  • Your IRS Online Account often shows notices the IRS has mailed. If you see the message there, the letter is almost certainly legitimate.
  1. Report suspected scams.

Practical examples from the field

  • Legitimate notice example: A client received a CP2000 stating additional income reported by an employer. We logged into the client’s IRS Online Account, found the same notice posted there, and then submitted documentation and a concise written response within the notice deadline. The balance was corrected without penalty.

  • Phishing example: Another client received a letter demanding immediate payment via wire transfer and listing a non‑irs website to resolve the issue. The formatting was inconsistent and the return address didn’t match typical IRS mail. We reported it to TIGTA and the client avoided a six‑figure scam attempt.

These cases show why verification—especially using IRS online tools and the official phone numbers—is essential.

How to respond when a notice is confirmed legitimate

  1. Read the notice carefully and note deadlines. Many notices include actions you can take to resolve the issue without escalating.
  2. Gather documentation that supports your position (W-2s, 1099s, bank statements, prior-year returns).
  3. If the notice requires payment, use secure IRS payment options (Direct Pay, EFTPS, or pay by check made out to the U.S. Treasury). Avoid prepaid cards and wire transfers unless explicitly confirmed as legitimate.
  4. If you disagree, reply in writing as instructed and include copies (never send originals). Send via tracked mail or other proof-of-delivery methods.
  5. Consider consulting a tax professional—especially for notices proposing tax increases, audits, or when legal filings may be required.

Who is affected

All taxpayers can receive IRS letters: individuals, sole proprietors, partnerships, corporations, and tax-exempt organizations. Certain notices—like identity verification letters—affect taxpayers with possible ID theft risk. Businesses may receive specialized payroll or employment tax notices.

Common mistakes and misconceptions

  • Mistake: Ignoring a letter because it “feels like a scam.” Many legitimate notices look alarming but require formal response. If you ignore a legitimate notice you can face penalties or enforced collection.
  • Mistake: Calling the number printed on a suspicious notice without verifying it. If the notice is a fake, the phone number will connect you to scammers.
  • Misconception: The IRS will email demanding immediate payment. The IRS does not initiate contact by email, text, or social media to request payment or sensitive personal information.

What to do if you’ve already responded to a likely fake notice

  • If you paid money or gave account details, immediately contact your bank or card issuer to try to stop the transfer or cancel the card.
  • File a complaint with TIGTA and the FTC; consider placing fraud alerts with the credit bureaus and monitoring accounts closely.
  • If you gave your SSN and suspect identity theft, request an Identity Protection PIN (IP PIN) from the IRS and follow IRS identity-theft guidance: https://www.irs.gov/identity-theft-fraud-scams.

Frequently Asked Questions

Q: Can I verify a notice by calling the number printed on it?
A: Only if you’re confident the printed number belongs to the IRS. When in doubt, call the IRS at 1-800-829-1040 (individuals) or use the option to schedule an appointment with an IRS representative. Cross-check phone numbers on IRS.gov.

Q: What if I missed the deadline on the notice?
A: Contact the IRS immediately to explain the situation; in many cases you can request penalty relief or set up a payment plan. If a statutory filing period passed, consult a tax attorney or tax pro quickly.

Q: How do I report a suspected IRS impersonation?
A: Report phishing and impersonation attempts to the IRS at https://www.irs.gov/privacy-disclosure/report-phishing and to TIGTA at https://www.treasury.gov/tigta/contact_report.shtml. You can also file a complaint with the FTC at https://reportfraud.ftc.gov/.

Quick verification checklist (printable)

  • Look for notice/letter number and tax year.
  • Compare the notice with IRS descriptions online.
  • Check your IRS Online Account for the same notice.
  • Call the IRS using a verified phone number.
  • Don’t pay with unconventional methods; use secure IRS payment channels.
  • Report suspected scams and keep records of any communications.

Helpful links and resources

Internal resources you may find useful:

Professional disclaimer

This article provides general information and is not personalized tax advice. Tax rules and IRS procedures change; verify phone numbers and procedures on IRS.gov or consult a licensed tax professional before taking action.

Authoritative sources

If you want, I can prepare a one‑page printable checklist you can keep with your financial records or draft a sample response letter to a common IRS notice.