Information For...

For you and your family
Standard mileage and other information

Forms and Instructions

Individual Tax Return
Instructions for Form 1040
Request for Taxpayer Identification Number (TIN) and Certification
Request for Transcript of Tax Return


Employee's Withholding Allowance Certificate
Employer's Quarterly Federal Tax Return
Employers engaged in a trade or business who pay compensation
Installment Agreement Request

Popular For Tax Pros

Amend/Fix Return
Apply for Power of Attorney
Apply for an ITIN
Rules Governing Practice before IRS

Understanding your CP11 Notice

We made changes to your return because we believe there's a miscalculation. You owe money on your taxes as a result of these changes.

Looking for information for CP11A Notice?

What you need to do

  • Read your notice carefully. It will explain the changes we made and why you owe money on your taxes.
  • If you agree with the changes we made.
    • Pay the amount owed by the date on the notice.
    • The Payments tab lists electronic payment options.
    • Make payment arrangements if you can't pay the full amount you owe. You can do this online using the Online Payment Agreement tool.
    • Correct the copy of your tax return that you kept for your records, but do not send it to us.
  • If you don't agree, contact us within 60 days from the date of your notice, and see common questions below.
    • By telephone: Call us at the telephone number shown on your notice. The fastest way to resolve many return errors is by telephone. Some cases require additional information that you may provide verbally. If we need a missing or corrected form or document, you can fax it to us while on the telephone. Either way, we may be able to correct your account immediately.
    • By mail: Please include a copy of the notice along with your correspondence or documentation, and allow 30-60 or more days for a resolution.

Answers to common questions

How can I find out what caused my tax return to change?
Read your notice carefully. For additional clarification, contact us at the number on your notice.

What should I do if I disagree with the changes you made?
If you disagree, contact us at the toll-free number on the top right corner of your notice, 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.

If you contact us within 60 days from the date of this notice, we'll reverse the change we made to your account. However, if you can't provide us additional information that justifies the reversal and we believe the reversal is in error, we'll forward your case for audit. This step gives you formal appeal rights, including the right to appeal our decision in court before you have to pay the additional tax. After we forward your case, the audit staff will contact you within five to six weeks to explain the audit process and your rights. If you don’t contact us within the 60-day period, you'll lose your right to appeal our decision before payment of tax.

If you don't contact us within 60 days, you must pay the additional tax before we will consider reversing the changes. You can then file a claim for refund. You must submit the claim within three years from the date you filed the tax return, or within two years from the date of your last payment for this tax.

Will I be charged interest on the money I owe?
To avoid interest charges, full pay the amount owed by the due date stated on the payment coupon. If you don't pay in full by that date, interest will accrue on the unpaid balance from the date the return was due.

Will I receive a penalty if I can't pay the full amount?
Yes, you will receive a late payment penalty. You can contact us at the number given on your notice if you can't pay the full amount shown in your specific notice because of circumstances beyond your control. Contact us by the due date of your payment and, depending on your situation, we may be able to remove the penalty. See our Penalty Relief page for what information to have available.

Tips for next year

Consider filing your taxes electronically. Filing online can help you avoid mistakes and find credits and deductions that you may qualify for. In many cases you can file for free. Learn more about e-file.

To help avoid the same issue next year, correct the copy of this year's tax return that you kept for your records. If you use a tax preparer, also have them correct their copy.