What this notice is about We made the changes you requested to your tax return for the tax year on the notice. You owe as a result of the changes. View this notice and manage your communication preference online Sign in to your Online Account to: View and download this notice Go paperless for certain notices Get email notifications for new notices What you need to do Read your notice carefully. It will explain why you owe. Contact us is you disagree with the changes we made. If you agree with our changes, correct the copy of your tax return that you kept for your records. Pay the amount you owe by the due date on the notice's payment coupon. Make payment arrangements if you can't pay the full amount you owe. Frequently asked questions The notice says, "Based on the information you provided, we changed your 20XX Form 1040 to correct your:...," but I don't remember sending any change to IRS. How can I find out what you received to make this change? Call us at the toll-free number listed on the top right corner of your notice. What do I say when I call the IRS? Mention that you received a CP21A notice with a balance due and you need to review your account. Be sure to have a copy of your notice and your tax return before you call. What should I do if I disagree with the changes you made? Call us at the toll-free number listed on the top right corner of your notice. What happens if I can't pay the full amount I owe? You can arrange to make a payment plan with us. Am I charged interest on the money I owe? Yes, interest will accrue if you don't pay the full amount you owe by the date on the payment coupon. Will I receive a penalty if I can't pay the full amount? Yes, you'll receive a late payment penalty. You can call us at the number listed on your notice if you’re unable to pay the full amount shown because of circumstances beyond your control. If you contact us by the due date of your payment, we may be able to remove the penalty, depending on your situation. What if I need to make another correction to my account? You'll need to file Form 1040-X, Amended U.S. Individual Income Tax Return. What if I haven't been able to get answers after contacting IRS several times? Call our Taxpayer Advocate Service at 877-777-4778 or for TTY/TDD 800-829-4059. What if I think I'm a victim of identity theft? Call us at the number listed on the top right corner of your notice. See our IRS Identity Theft resource page for more information. 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. Helpful information Notice 746, Information About Your Notice, Penalty and Interest PDF Form 9465, Installment Agreement Request PDF Reference tools Publication 1, Your Rights as a Taxpayer Notice Topic 651 Notice Topic 653 Full list of tax forms and instructions Need help? You can authorize someone to represent you before the IRS or inspect and/or receive confidential tax information. You may be eligible for free help from the Taxpayer Advocate Service (TAS). See if you qualify for help from a Low Income Taxpayer Clinic. You can request a copy of your notice or letter in Braille or large print. If you can’t find what you need online, call the telephone number on your notice or letter.