Identity Verification Common Questions

FAQ Index

    Frequently Asked Questions

    Why is the Illinois Department of Revenue (IDOR) sending me this letter?

    We want to protect you and your identity. This is a safeguard to prevent someone from using your identity to file a false tax return.

    Why was my return selected for additional review?

    We received an Illinois Individual Income Tax Return, filed with your Social Security number (SSN) or Individual Taxpayer Identification number (ITIN). In order to protect your identity, we are requiring you to verify your information to ensure that you are the individual who filed this return.

    What should I do if I received an Identity Verification letter?

    Your letter has specific instructions for you to follow to verify your identity.

    What do I do if I did not file this return?

    1. Go to our website at
    2. scroll down to the section titled "Identity Verification", 
    3. select the Identity Verification Code link, 
    4. select "No, I did not file this return and need to report identity theft"
    5. enter your contact information, and 
    6. click Submit.

    I did not verify my identity by the due date. What should I do?

    You must submit two required documents to verify your identity - one from each category listed below, within 60 days of the date of this letter.

    Category 1: Submit one document that has your photograph and full name:

    • Illinois driver’s license (current or expired less than one year)
    • Driver’s license from any other state (current)
    • State identification card
    • Passport
    • Military identification
    • Government issued photo identification
    • U.S. high school, college or university photo ID
    • Employee photo ID card with recent payroll stub
    • Valid Photo ID of 3rd Party Designee


    Category 2: Submit one document that has your full name and complete address used on the tax return filed:

    • Utility bill (gas, electric, cable, cell phone, etc.)
    • Bank statement
    • Payroll stub or W-2
    • Property tax bill
    • Rental agreement (signed by landlord and renter)
    • College or university transcript
    • Insurance policy (vehicle, homeowners, renters, health, life)
    • Credit card statement
    • Death Certificate
    • Birth Certificate

    You may submit the documents

    1. Electronically - Go to our website at, scroll down to the section titled "Identity Verification", select the Identity Verification Documents link, enter your Letter ID, and follow the instructions.
      Note: Submitting your information electronically will result in a quicker and more secure process. However, if you do not have a Letter ID, you must submit your documents by mail.
    2. By mail - send a copy of the letter (or Form IL-425 if you do not have the letter) and copies of the required documents to
      PO BOX 19049
      SPRINGFIELD IL 62794-9049
      Warning: Do NOT mail original documents; we accept copies.

    If you have questions, call Taxpayer Assistance at 800 732-8866 and a representative will
    assist you. Our hours are Monday through Friday from 8:00 AM to 5:00 PM.

    I do not have access to a computer, or I am having difficulty verifying my identity electronically. What should I do?

    Follow the instructions under the question “I did not verify my identity by the due date. What should I do?” for submitting documents to verify your identity by mail.

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