Information For...

For you and your family
Standard mileage and other information

Forms and Instructions

Individual Tax Return
Instructions for Form 1040
Request for Taxpayer Identification Number (TIN) and Certification
Request for Transcript of Tax Return


Employee's Withholding Allowance Certificate
Employer's Quarterly Federal Tax Return
Employers engaged in a trade or business who pay compensation
Installment Agreement Request

Popular For Tax Pros

Amend/Fix Return
Apply for Power of Attorney
Apply for an ITIN
Rules Governing Practice before IRS

Understanding Your CP20 Notice

We believe you incorrectly claimed one or more deductions or credits. As a result, your refund is less than you expected.

What you need to do

  • Review your notice and compare our changes to your tax return.
  • Complete and return the Response form.

You may want to

  • Review this notice with your tax preparer.
  • Read about the deduction or credit we changed in Publication 17, Your Federal Income Tax.

Answers to common questions

What is the notice telling me?
Based on the information shown on your tax return, it appears you didn't meet the requirements for claiming one or more deductions or credits. As a result, your refund is less than you expected.

What do I have to do?
Review the requirements for the deduction or credit we adjusted. Return the Response form indicating whether you agree or disagree with the changes.

If you feel your tax return was correct as filed, send us the documentation listed on page 2 of the notice to verify you qualify for the exemption or credit.

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.

Printable samples of this notice (PDF)

How to get help