Understanding your CP163 notice

 

What this notice is about

This notice reminds you that you still have a balance due and it requires your immediate attention.


What you need to do

  • Read your notice carefully. It explains how we calculated your amount due.
  • Compare the figures on the notice with your tax return.
  • Check the list of payments we applied to your account to verify if we applied all the payments you made.
  • Pay the amount due by the date on the notice.
  • Request a payment plan if you can't pay the full amount you owe.
  • Contact us if you disagree by calling the toll-free number shown on your notice.

You may want to

Learn more information about:


Frequently asked questions

Will I be charged additional interest on the amount I owe? (updated Feb. 27, 2026)

We don’t charge additional interest if you pay the full amount you owe by the payment due date found on the notice. However, interest will continue to increase on the unpaid balance after the payment due date.

Will I receive a penalty if I can't pay the full amount? (updated Feb. 27, 2026)

Yes. You’ll receive a late payment or failure to deposit penalty, depending on what you owe. Notice 746, Information About Your Notice, Penalty and Interest PDF, has more information about penalties and interest.

What happens if I can't pay the full amount I owe? (updated Feb. 27, 2026)

You can request a payment plan if you can't pay the full amount you owe. Call us at the toll-free number on your notice to discuss payment options or learn more about them.

What should I do if I disagree with the notice? (added Feb. 27, 2026)

Contact us at the toll-free number on your notice. Have your documentation such as canceled checks, amended return, etc. ready when you call.


Tips for next year

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


Helpful information

Need help?