Understanding your CP133 notice

What this notice is about

We made changes to your tax return because we believe there's a miscalculation on your return. As a result of these changes, there's an overpayment on your account.

What you need to do

• Read the notice carefully. It will explain the changes we made.
• Compare the figures on the notice with your tax return.
• If you agree with the changes we made, correct the copy of your tax return that you kept for your records.
• If you don't agree with the changes, contact us within 10 days from the date of your notice by calling the toll-free number listed on your notice or by mailing the completed contact stub with any correspondence or documentation.
• If you haven't already, you should receive a refund of the overpayment within four to six weeks if you owe no other taxes or debts we're required to collect. You don't need to take any further action.

Frequently asked questions

Tips for next year

• Refer to the instructions for your tax return for required documentation and how to complete your return. Attach all required forms and schedules to your tax return when filing.
• Consider filing your taxes electronically. Filing online can help you avoid mistakes and save you time.

Helpful information

• Publication 505, Tax Withholding and Estimated Tax
• Publication 542, Corporations
• Publication 559, Survivors, Executors, and Administrators
• Publication 598, Tax on Unrelated Business Income of Exempt Organizations
• Notice 746, Information About Your Notice, Penalty and Interest PDF