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Published:   |   Last Updated: June 16, 2023

Were Errors Found on Return

Letter 12C

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Station Overview

The IRS needs more information before it can process your return.

This notice or letter may include additional topics that have not yet been covered here. Please check back frequently for updates.



This is a 20 day notice, please enter the date of your notice so we can help you determine how much time you have left to pay

What does this mean to me?

The IRS received your individual income tax return but more information is needed to process the return accurately.

A reply is needed within 20 days from the date of this letter. If the IRS doesn’t receive a response from you, an adjustment will be made on your account that may increase the tax liability that you will owe or reduce the amount of your refund.

How did I get here?

You submitted your income tax return that was not able to be processed. A letter is being sent to you because more information is needed to complete the processing of your individual income tax return. This information can include:

  • An illegible, missing or damaged form that cannot be processed.
  • Missing, illegible or damaged forms or schedules to support your entries on Form 1040. The original form must be resubmitted along with your original signature and all applicable schedules.
  • The required, complete Social Security numbers (SSNs) or individual taxpayer identification numbers (ITINs) are not on your return.
  • Verification of income, withholding, and/or credit amounts
  • Documentation is needed to reconcile advance payments of the Premium Tax Credit (PTC). Please refer to PTC page for more information about letters regarding advance payments of the PTC.

What are my next steps?


Verify the return address on the notice

The first thing to do is to check the return address to be sure it’s from the Internal Revenue Service and not from another agency, and not some type of a scam to obtain personal information from you.

Read the letter carefully and respond timely. If you need additional information, contact the IRS at the toll-free number listed on the top right corner of the letter.


Respond to the letter

Respond to the letter, even if you disagree with the information in the letter. If you disagree, send the IRS a letter explaining what information you think is in error. Provide the information requested in the letter.

Enclose only the information requested and any forms, schedules or other information required to support your entries and a copy of this letter. Don’t send a copy of your return unless the IRS asks you to do so. Do not file a Form 1040-X, Amended U.S. Individual Income Tax Return. After  the IRS receives the requested information, they’ll use it to process your original tax return.


You may have a refund, adjustment or have a balance due

If you’re entitled to a refund, the IRS will send it about six to eight weeks from the time they receive your response.

If the adjustment to your account results in a balance due, pay the amount you owe by the due date on the letter. If you are not able to pay the full amount by the due date, pay as much as you can to limit penalties and interest. Visit Paying Your Taxes to consider online payment options. If you need additional assistance, call the IRS at the toll-free number on the top right corner of your letter.

If you choose, you may be represented by an attorney, certified public accountant, or a person enrolled to practice before the IRS. Also, you may be represented by a member of your immediate family.  If you want your representative to contact us or appear without you and to receive and inspect confidential material, you must file a properly completed Form 2848 (no earlier than 10/2011 revision), Power of Attorney and Declaration of Representative. You may also authorize an individual to receive or inspect confidential material but not represent you before the IRS, by filing a Form 8821, Tax Information Authorization. These forms are available at your local IRS office, by calling 1-800-829-3676, or from www.IRS.gov.

Where can I get additional help

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If you still need help

The Taxpayer Advocate Service is an independent organization within the IRS that helps taxpayers and protects taxpayers’ rights. We can offer you help if your tax problem is causing a financial difficulty, you’ve tried and been unable to resolve your issue with the IRS, or you believe an IRS system, process, or procedure just isn’t working as it should. If you qualify for our assistance, which is always free, we will do everything possible to help you.

Visit www.taxpayeradvocate.irs.gov or call 1-877-777-4778.

Low Income Taxpayer Clinics (LITCs) are independent from the IRS and TAS. LITCs represent individuals whose income is below a certain level and who need to resolve tax problems with the IRS. LITCs can represent taxpayers in audits, appeals, and tax collection disputes before the IRS and in court. In addition, LITCs can provide information about taxpayer rights and responsibilities in different languages for individuals who speak English as a second language. Services are offered for free or a small fee. For more information or to find an LITC near you, see the LITC page on the TAS website or Publication 4134, Low Income Taxpayer Clinic List.

Where am I in the Tax System?

Were Errors Found on Return

Letter 12C