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Got an IRS CP12 Notice? What It Means and What to Do
A CP12 means the IRS corrected something on your return and your refund is different from what you expected. If the correction is right you do nothing. If it is wrong, you need to call by the date on the notice.
Reviewed by LaToya Clark-Thompson, FounderLast updated
What this letter is
The CP12 tells you the IRS corrected one or more mistakes on your return, and as a result your refund is different from the amount you claimed, or you are due a refund when you expected to owe or break even. It explains what changed.
It is the refund-side version of the CP11, which is sent when a correction leaves you owing.
Why you got it
- A calculation or transfer error between schedules
- A credit, such as the child tax credit or earned income credit, was adjusted because information was missing or did not match IRS records
- Estimated payments or an applied overpayment from the prior year did not match what the IRS shows
- Withholding on a W-2 or 1099 was entered differently from what the employer or payer reported
A smaller refund is not always an error on your side. Sometimes it is the IRS correcting in your favor, for example finding a payment you left off.
What to do now
- Compare what the IRS changed with your copy of the return and the forms behind it
- If you agree, you do not need to respond. Update your own copy of the return, but do not mail it to the IRS
- If you disagree, call the toll-free number listed under "Where to find more information" before the date on the notice. The IRS says calling is the quickest way to resolve most errors, and you can fax documents during the call
- If you have a separate correction to make, file Form 1040-X
If the refund is smaller because it was applied to a debt, such as past-due taxes or other government debts, that is a different process. Refund taken for a debt explains it.
What happens if you ignore it
If you agree, nothing: the refund is issued at the corrected amount, unless you owe other taxes or debts the IRS has to collect. If you disagree and do not call by the date on the notice, you lose your formal right to have the change reversed and to appeal to the U.S. Tax Court. The IRS will still consider documents you send later, but you are then asking for a reconsideration rather than a reversal.
How we help
We compare the change with your return, your forms and the IRS transcript and tell you whether it is right. If it is, we show you why, so next year’s return avoids it. If it is not, we put together the records that support the original figure. If something else on the return needs fixing, we prepare the amended return.
If a reversal request is referred to audit, the IRS says it will contact you. Representation from there is handled by the independent licensed CPA we work with, with our office coordinating. See IRS audit defense.
What to send us
- A photo or scan of every page of the CP12, through the client portal
- The return as filed
- The forms behind the line the IRS changed: W-2s, 1099s, estimated payment confirmations, dependent records
Frequently asked questions
Why is my refund smaller than I expected after a CP12?
The CP12 says the IRS corrected one or more mistakes on the return, and the notice explains which lines changed. Common causes are a credit that did not match IRS records, estimated payments or withholding that differed from what the IRS has, or a calculation error. If the refund was instead applied to a debt you owe, you would get a separate offset notice.
Do I have to respond to a CP12 if I agree?
No. If you agree with the correction, you do not need to contact the IRS. The refund is issued at the corrected amount unless you owe other taxes or debts it has to collect. Update your own copy of the return so next year’s figures, such as an applied overpayment, start from the right number.
How do I dispute a CP12?
Call the toll-free number on the notice before the date it gives. The IRS says it grants most reversals of reduced refunds on request, although supporting documents can speed things up, and you can fax them during the call. If the IRS does not receive information supporting your original return, it may refer the case to audit.
Can a CP12 increase my refund?
Yes. A CP12 is also sent when the correction gives you a larger refund than you claimed, or a refund when you expected to owe or break even. That usually means the IRS found a payment or credit you left off. Check it against your records anyway, and keep the notice with your return.
Not the question you had? The full tax FAQ covers more ground, and our client reviews say what the work is actually like.
Related pages
CP11 notice
The IRS changed your return and now you owe. Check the change and call by the date if you disagree.
Learn moreCP05 notice
The IRS is verifying parts of your return before releasing a refund. Usually a wait, not a problem.
Learn moreHow to read an IRS letter
Where the notice number, tax year, amount and response date sit on the page, and what each means.
Learn moreHow to respond to an IRS letter
Check it, decide whether you agree, gather support, reply by the date, and keep proof.
Learn morePart of IRS & SC Letter Help. Not sure which service fits? Answer a few questions.
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