Article: 50304
Overview – Rejection Code: IL1040-8100-1
Reason: The Illinois Department of Revenue (IDOR) rejected the return because the prior year Adjusted Gross Income (AGI), or Illinois Driver’s License/State ID information used to validate the electronic signature does not match IDOR’s records.
This error is common when:
- The AGI entered is incorrect or rounded improperly.
- The IL-PIN or ID information does not match what the state has on file.
- The taxpayer is a first-time filer, and ID verification is incomplete or invalid.
Steps to Resolve
Option 1: Use a Valid Illinois Driver’s License or State ID
If you have an Illinois driver’s license or state-issued ID, use it to sign the return instead of the AGI or IL-PIN.
Make sure:
- The name, license number, issue date, and expiration date are entered exactly as shown.
- You do not use nicknames or abbreviations.
Option 2: Confirm Prior-Year IL AGI
If signing with prior-year AGI:
- Refer to your Form IL-1040 from the previous tax year, Line 1.
- Make sure to enter the exact dollar amount, without cents, and do not round.
- If you did not file an IL return last year, use “0” as your AGI.
Option 3: Use or Retrieve IL-PIN
If eligible, you may use your IL-PIN instead of AGI or ID.
To retrieve your IL-PIN:
- Visit the MyTax Illinois PIN Inquiry
- Or call IDOR at 800-732-8866
First-time Illinois filers: You will not have a prior-year AGI or IL-PIN. You must use a valid state ID.
Name changes or address changes from the prior year may cause validation issues.
Steps to Correct
Go back through the e-file process to correct the AGI or ID information in your return. If the issue persists, the return may need to be printed and mailed with a signature.
Additional Resources
- Visit tax.illinois.gov for additional guidance.
- Contact IDOR at 800-732-8866 for assistance.