What this letter is about

We are sending you Letter 12C because we need more information to process your individual income tax return. This information can include:

  • Missing forms or schedules to support your entries on Form 1040, 1040-SR1040-A, or 1040-EZ
  • Verification of income, withholding, and credit amounts
  • Documentation to reconcile advance payments of the Premium Tax Credit (PTC). Please refer to PTC page for more information on PTC advance payments.

What you need to do

  • Read your letter carefully and respond timely.
    • Respond to the letter, even if you disagree with the information in it.
    • Send us a letter explaining what information you think is in error.
    • Send the information we requested.
  • Do not file a Form 1040-X, Amended U.S. Individual Income Tax Return. When we receive the requested information, we’ll use it to process your original tax return.
  • If you’re due a refund, we’ll send it about 6-8 weeks after we receive your response.

How to respond

  • Fax your information to the fax number in the letter or mail your information to the address shown at the top of the letter.
  • Include a copy of the letter with your response.

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