IRS Notice CP01C: Incorrect IP PIN Used
The Identity Protection PIN on your return didn't match IRS records.
- Response deadline
- 30 days from the notice date
- Category
- Identity & Security
- Severity
- Moderate
What does an IRS CP01C notice mean?
A CP01C indicates that the Identity Protection PIN entered on your return did not match the IP PIN the IRS issued to you, so the IRS could not verify the return. Processing is paused until the correct PIN is supplied.
Why did you receive a CP01C?
An incorrect or outdated IP PIN was used — for example, last year's PIN instead of the current one, or a typo during filing.
How to respond to a CP01C notice
Retrieve your correct, current IP PIN through your IRS online account or the IRS 'Get an IP PIN' tool, then refile or follow the notice's instructions to provide the right number. Make sure you are using the PIN for the correct tax year.
What happens if you ignore it?
Your return will not finish processing and any refund stays delayed until the correct IP PIN is provided.
Common resolutions
- Retrieve the correct IP PIN
- Refile with the correct PIN
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For informational purposes only. Not legal, tax, or medical advice.