IRS Notice CP11: Changes to Tax Return — Amount Owed

What does an IRS CP11 notice mean?

A CP11 tells you the IRS changed your return because it found a miscalculation, and the change resulted in a balance due. The notice explains the specific adjustment — for example, a math error, a disallowed credit, or a corrected figure — and shows the new amount you owe with penalties and interest.

Why did you receive a CP11?

Common triggers include arithmetic mistakes, claiming a credit you did not qualify for, entering income or withholding incorrectly, or a dependent or Social Security number that did not match IRS records.

How to respond to a CP11 notice

If you agree with the correction, pay the balance by the due date or set up a payment plan. If you disagree, you generally have 60 days to contact the IRS to dispute the change and request that the original figures be reinstated — acting within 60 days preserves important rights. Provide documentation supporting your original return.

What happens if you ignore it?

The balance becomes final, penalties and interest accrue, and the account moves into the standard collection sequence (reminders, then levy notices). Disputing after the 60-day window is harder and may require paying first and then claiming a refund.

Common resolutions

• Pay the balance
• Dispute the changes
• Request abatement

Related IRS notices

• CP12 — Correction Resulted in Overpayment
• CP13 — Refund Adjustment — No Refund Due
• CP21B — Adjusted Return — Balance Due
• CP22A — Adjustment — Amount Due