What this letter is about Letter 6167C tells you we need to verify your identity to process a federal income tax return filed with your name and taxpayer identification number. What you need to do Call the Taxpayer Assistance Center toll-free at the number on your letter. If you are out of the country, mail your response with the requested information within 30 days. Bring the following to your appointment: The 6167C letter The income tax return referenced in the letter (Form 1040, 1040A, 1040-EZ,1040-PR, 1040-NR, etc.)Note: A Form W-2 or Form 1099 is not a tax return. A previous year’s income tax return, other than the year in the letter (Form 1040, 1040A, 1040-EZ,1040-PR, 1040-NR, etc.).Note: A Form W-2 or Form 1099 is not a tax return. Supporting documents that you filed for each year’s income tax return (Form W-2, Form 1099, Schedule C or F, etc.). Bring the following Identity Verification Documents to your appointment: A valid U.S. federal or state government-issued picture identification, such as a driver’s license, state ID, or passport. At least ONE of the following forms of identification: Current U.S. federal or state government-issued identification that is different from the first document above; U.S. Social Security card; mortgage statement with current address; Lease agreement for a house or apartment with current address; Car title; Voter registration card (not the voter registration application); Utility bill with current address; Birth certificate (the IRS no longer accepts Puerto Rican birth certificates issued before July 1, 2010); Current school records. You may want to Review this notice with your tax preparer. Contact Taxpayer Advocate Service (TAS) if you’re experiencing an economic hardship or need help in resolving problems. You can reach TAS at 877-777-4778 or TTY/TTD 800-829-4059. What if you don't respond We may not be able to process your return, issue refunds, or apply overpayments to next year’s estimated tax. Frequently asked questions What happens after my appointment or after I have mailed the documentation? Once we verify your identity and confirm you submitted the tax return, we’ll continue processing your return. It will take about nine weeks to process. What if I didn’t file the tax return? Someone else may have filed it for you without your consent. Send us a completed and signed Form 14039, Identity Theft AffidavitPDF. You may want to read our identity theft resources page while we review your Form 14039. Reference tools Publication 1, Your Rights as a Taxpayer Publication 17, Your Federal Income Tax Full list of tax forms and instructions 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, call the IRS number at the top of your notice or letter. If you didn’t receive a letter or notice, use telephone assistance. If you can't resolve the penalty on your own, contact Taxpayer Advocate Service, an independent organization within IRS.