Skip to main content

Scam Alert: Fake Texts and Websites Impersonating IDOR

Be alert for fraudulent messages or websites attempting to steal your banking information, login credentials, or credit card details. The Illinois Department of Revenue (IDOR) will never request personal or financial information via text message. To confirm official communications or contact details, always visit https://tax.illinois.gov.

Employment Sign Up for Updates

2026 IL-941 Illinois Withholding Income Tax Return

Important: This form is required to be filed electronically. Electronic mandate

Filing online is quick and easy!

  • File your IL-941 online
    If you are unable to file electronically, you may request Form IL-900-EW, Waiver Request, through our Taxpayer Assistance Division at 800-732-8866 or 217-782-3336. The Waiver Request must be completed and submitted back to the Department. You will be notified if the Waiver Request is approved or denied.
  • Right click here and "save as" to download the 2026 PDF form. Then open the saved PDF file using Adobe Acrobat.