What are common reasons for IRS letters?

Asked by: Prof. Tabitha Marquardt V  |  Last update: July 23, 2026
Score: 4.6/5 (3 votes)

Common IRS letters (notices) are sent for balances due, discrepancies in reported income, identity verification, or adjustments to refunds/returns. They often request additional information, notify taxpayers of processing delays, or explain changes made to a filed return. Most letters require prompt action, such as payment or responding by a specific date.

What triggers an IRS letter?

A notice may reference changes to a taxpayer's account, taxes owed, a payment request or a specific issue on a tax return. Taking prompt action could minimize additional interest and penalty charges.

What is the most common reason for an IRS letter?

We may send you a notice or letter if:

  • You have a balance due.
  • Your refund has changed.
  • We have a question about your return.
  • We need to verify your identity.
  • We changed or corrected your return.
  • We're delayed in processing your return.

What kind of mail comes from the IRS?

You might receive IRS mail for a variety of reasons–it could be about your tax return, a payment, or a notice of a discrepancy. Make sure you read it carefully and respond if needed. Usually, the notice will include instructions.

What do IRS audit letters look like?

An IRS audit letter typically contains the taxpayer's name, tax ID number, contact information, and a request for additional documentation to support claims on the tax return. It may also include the name of the IRS officer handling the case and invite the taxpayer to a meeting.

IRS Tax Notices and Tax Letters Explained - Step-by-Step breakdown

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How can I find out what letter the IRS sent me?

You can find digital copies of most IRS notices in your online account, under the 'Notices and Letters' section.

Where would an IRS letter come from?

We typically contact you the first time by mail delivered by the U.S. Postal Service. To verify it's us, search IRS notices and letters. Some letters are sent from private collection agencies.

How do you know if the IRS is investigating you?

You know the IRS might be investigating you through official mail (first contact), phone calls (often with automated messages to IRS.gov), or in-person visits, but signs of a criminal probe include contact with IRS Criminal Investigation (CI) agents, subpoenas to you or your bank, questions to your accountant/bank, unusual account activity (freezing/refusing transactions), or agents suddenly going silent after an audit. Key indicators are official IRS letters, contact from CI special agents, third-party inquiries, and formal summonses for records, signaling serious scrutiny beyond a simple audit. 

Does IRS send audit letters by regular mail?

The IRS is a government agency and the audit letter is sent by certified mail.

Can I ignore an IRS notice?

Here's what happens if you ignore the notice:

The IRS will make changes to your return (like adding income or removing deductions and/or credits). The IRS will propose taxes and possibly penalties, and you'll get a “90-day letter” (also known as a statutory notice of deficiency).

How to identify a real IRS letter?

To tell if an IRS letter is real, check for typos and poor grammar, verify it contains specific personal info (like the last 4 of your SSN), look for an official notice number (CP or LTR) and logo, and ensure it doesn't demand immediate payment via gift cards or threaten arrest, as scammers do. If in doubt, log into your secure IRS Online Account or call an official IRS phone number (not one from the letter) to verify.

Is it always bad news when you get a letter from the IRS?

Most IRS letters and notices are about federal tax returns or tax accounts. Each notice deals with a specific issue and includes specific instructions on what to do. Don't panic. The IRS and its authorized private collection agencies do send letters by mail.

How do I respond to an IRS letter?

How to Respond to a Letter From the IRS

  1. First read the letter in its entirety. ...
  2. Print and complete any required forms. ...
  3. Gather any supporting documents. ...
  4. Draft a response letter to the IRS, outlining any claims that you dispute.

How many notices does the IRS send before a lien?

The IRS waits to record most tax liens until after it has sent all five notices in the collection notice stream and hasn't received payment. You'll want to avoid a Notice of Federal Tax Lien. Liens can affect your ability to attract new business clients, secure and maintain credit, and obtain employment.

What looks suspicious to the IRS?

Not reporting all of your income is an easy-to-avoid red flag that can lead to an audit. Taking excessive business tax deductions and mixing business and personal expenses can lead to an audit. The IRS mostly audits tax returns of those earning more than $200,000 and corporations with more than $10 million in assets.

Will you be notified if you are under investigation?

The government has no legal obligation to notify you that you're under investigation. There is no constitutional right to know that prosecutors are building a case against you.

What should I do if I get an IRS letter?

Check which tax year the notice is for and follow the instructions provided; you usually have 30 days to respond. Compare the IRS adjustments to your records and tax return. If you agree with the notice, indicate that on the response form and send a check or money order for any additional taxes due.

What do IRS audit envelopes look like?

The audit notice will usually come in a plain white envelope with a clear insert to show your name and address. The audit notice will not have a postage stamp on it. It will have a postage meter stamp on it or have no postage at all. These are clues that the notice is actually from the IRS.

What triggers an IRS audit letter?

Unreported income

The IRS receives copies of your W-2s and 1099s, and their systems automatically compare this data to the amounts you report on your tax return. A discrepancy, such as a 1099 that isn't reported on your return, could trigger further review.

Why am I getting a letter from the IRS in 2025?

A notice may reference changes to a taxpayer's account, taxes owed, a payment request or a specific issue on a tax return. Taking prompt action could minimize additional interest and penalty charges.

Can I ignore an IRS letter?

If a taxpayer receives an IRS letter or notice, they should: Not ignore it. Most IRS letters and notices are about federal tax returns or tax accounts. The notice or letter will explain the reason for the contact and gives instructions on what to do.