Understanding your CP12G or CP12U notice


What this notice is about

We found a miscalculation and changed your return to correct this error. You're now due a refund.

What you need to do

  • Review the notice and compare our changes to your tax return.
  • If you agree with the changes, no response is required
    • You should receive a refund check in 4-6 weeks, if you don't owe other tax or debts we're required to collect.
  • If you don't agree with the changes, contact us within 60 days from the date of your notice.

Frequently asked questions

We issue CP12G or CP12U when we correct one or more mistakes on your tax return, and

  • The overpayment is different than you expected, or
  • You have an overpayment when you thought you owed money or had an even balance

Call us at the toll-free number shown on your notice.

If you disagree, contact us at the toll-free number or respond by mail to the address on your notice. If you write to us, include a copy of the notice along with your correspondence or documentation.

You must contact us within 60 days of the date of your notice to request a reversal. Provide an explanation or additional documents you want us to consider when requesting a reversal. If we don't receive your supporting documents we may forward your case for audit. Audit staff will contact you within 6-12 weeks to explain the process and your rights.

If you don't contact us within the 60-day period, changes we made to reduce your refund won't be reversed and you'll lose your right to appeal our decision in the U.S. Tax Court. Instead, you may file a claim for refund to dispute the changes. Generally, you must submit the claim within 3 years from the date you filed the tax return, or within 2 years from the date of your last payment for this tax — whichever is later.

Helpful information

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