Illinois
Last Updated June 17, 2026.
Access Illinois payroll tax resources, employer registration links, withholding and unemployment tax information, and agency contacts from Payentry.
State Tax Guidelines
Illinois Department of Revenue – Withholding Tax
Agency Information
Add to existing company setup
Submit a request to your service team to add IL (withholding) to your company setup. Please include the below with your request:
- Withholding – Withholding account number and Deposit Frequency. If you’re unsure of your deposit frequency or account number you can call the agency at 217-782-3336.
- Power of Attorney- POA is required, please obtain the prefilled form from your client service representative.
Register a new company
Illinois Department of Employment Security – Unemployment tax
Agency Information
Add to existing company setup
Submit a request to your service team to add ILSUI (unemployment) to your company setup. Please include the below with your request:
- Unemployment – Account Number and Tax rate. This can be found on a Tax Rate Notice or the Quarterly contribution report. If you’re unsure of your tax rate or account number, you can call the agency at 800-247-4984.
- Power of Attorney – POA is required, please obtain the prefilled form from your client service representative.
Register a new company
Managing employees in multiple states?
Payentry helps businesses handle payroll processing, tax filing, new hire reporting, and compliance requirements across all 50 states. Learn how our payroll solutions can simplify multi-state payroll management.
