Understanding Your Letter 5071C or 6331C

What this letter is about

Verify your identity to process a federal income tax return filed with your name and taxpayer identification number.


What you need to do immediately

Go to our secure Identity Verification Service to verify your identity. It’s quick, secure, and available 24 hours a day.

  • You must register to the website before verifying your identity. Be sure to check the website and prepare all the documents needed to complete the registration.
  • Have a copy of the 5071C or 6331C letter you received and a copy of the tax return for the tax year shown in the letter.
  • If you did not file an income tax return, you can indicate that on the website.

If you want to call us

If you prefer to talk to our representative, call the toll-free IRS Identity Verification telephone number in the 5071C or 6331C letter.

Note: Although the letters request a response within 30 days, the IRS will continue to work with you regardless of the amount of days that have passed.

Have ALL of the following available when you call:

  • The 5071C or 6331C letter;
  • The tax return referenced in the letter (the Form 1040 series return). Note: A Form W-2, Form 1099 is not a tax return;
  • A prior year’s income tax return, other than the year in the letter, if you filed one. Note: A Form W-2, Form 1099 is not a tax return; and
  • Supporting documents that you filed with each year’s tax return. (Form W-2, Form 1099, Schedule C or F, etc.).

Note: Authorized third parties may assist taxpayers, but the taxpayer must call us together and must participate on the call.

The toll-free number IRS Identity Verification number is for identity verification only. No other tax-related information, including refund status, is available.


Frequently asked questions

What if I am incarcerated?

You must coordinate with your Prison Official.

What happens if I do not verify immediately?

Until we hear from you, we won’t be able to process your tax return, issue refunds, or credit any overpayments to your account.

What happens if I cannot verify?

If we can’t verify your identity online or over the phone, we will ask you to schedule an appointment and bring the documents listed above to your local IRS office to verify in person.

What happens after I successfully verify?

If we successfully verify your identity, we’ll process your tax return. It will take up to 9 weeks to receive your refund or credit any overpayment to your account. However, if we find other problems, we’ll contact you again. This will delay your refund more.

Why am I getting this letter?

IF YOU DIDN’T FILE: Someone may have filed a fraudulent tax return using your name and SSN or ITIN. If you didn’t file an income tax return for the year above, it is important to let us know on the website above immediately and confirm that you may be victim of identity theft to stop further fraudulent activities.

IF YOU DID FILE: Contact us through the website above - we just need more information from you to verify your identity and process your income tax return, issue a refund, or apply the overpayment to your next year’s estimated tax.

Where can I find more information?

You can find more information in Publication 5027, Identity Theft Information for Taxpayers PDF or on IRS.gov/id.

The IRS Identity Protection PIN can help prevent misuse of your taxpayer identification number on fraudulent federal income tax returns. Learn more at IRS.gov/ippin.