Understanding Your CP51A Notice


What this notice is about

We computed the tax on your Form 1040 or 1040-SR. You owe taxes.

What you need to do

  • Read your notice carefully. It will explain how much you owe and how to pay it.
  • Pay the amount due by the date shown in the notice.
  • Make payment arrangements if you can't pay the full amount you owe.
  • Contact us if you disagree with the amount of tax we computed.

You may want to

Frequently asked questions

You can make a payment plan.

Call us at the toll free number on the top right corner of your notice to talk about payment plans or learn more about them.

Call us at the toll-free number on the top right corner of your notice. Please have your paperwork (such as cancelled checks, amended return, etc.) ready when you call.

Not if you pay the full amount you owe by the date on the payment coupon. However, interest will be charged if you pay after that date, even if you get a payment plan.

Yes, you'll receive a late payment penalty. You can call us at the number on your notice if you can't pay the full amount because of financial problems. Contact us by your payment's due date. Based on your situation, we may be able to remove the penalty.


Helpful information

Tips for next time you file

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.

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