Understanding Your CP105 Notice

What this notice is about

We made changes to your tax return because we found a miscalculation. As a result of these changes, you have a balance due.


What you need to do

  • Read the notice carefully.
  • Compare the figures on the notice with your tax return.
  • Contact us within 10 days of the date of your notice if you disagree with the changes we made.
  • Correct the copy of your tax return you kept for your records if you agree with our changes.
  • Pay the amount you owe by the payment due date on the notice.

  • Contact us to make payment arrangements if you can’t pay the amount you owe. Learn about payment options.

You may want to

  • Download copies of the following materials (if they weren’t included with your notice):

Answers to common questions

How can I find out what caused my tax return to change?

Call us at the toll-free number on your notice for specific information about your tax return.

What should I do if I disagree with the changes you made?

If you disagree, call us at the toll-free number on your notice or write to us at the address on the contact stub within 10 days of the date of the notice. We can reverse the change to your account if your response provides additional information that justifies a reversal. If you agree with the change, pay the balance due or make payment arrangements by the payment due date on the notice.

What happens if I can’t pay the full amount I owe?

You can request a payment plan if you can’t pay the full amount you owe. Learn more about payment options.

Am I charged interest on the money I owe?

We don’t charge interest if you pay the full amount you owe by the payment due date on the notice. However, interest accrues on the unpaid balance after that date.

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 toll-free number on your notice if you can’t pay the full amount due 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.


Tips for next year

  • Consider filing your taxes electronically. Filing online can help you avoid mistakes. Learn more about e-file.
  • Review your return for accuracy prior to mailing it to us.

Printable samples of this notice (PDF)

Need Help?

  • You can authorize someone to contact the IRS on your behalf.
  • See if you qualify for help from a Low Income Taxpayer Clinic.
  • If you can’t find what you need online, you can call the IRS at the 800, 866, or 888 number listed on the notice.