Illinois State Tax Information

Withholding Requirements:

  • Register new businesses by filing Form REG -1 (Business Registration Application)
  • Employee’s Illinois Withholding Allowance:  IL-W4
  • Withholding Method = 4.95% effective 7/1/17, still in effect for 2019
  • Supplemental Rate = Withhold at 4.95% effective 7/1/17, still in effect for 2019

Local Taxes:

None

State Unemployment Insurance (SUI):

Register as employer by filing Form UI-1 (Report to Determine Liability)
Report quarterly wages and contributions by filing Form UI-340 Employer’s Contribution and Wage Report) by last day of month following end of quarter.

Wage base is $12,960 for 2019
Rates range from 0.475% to 6.875% for 2019
New employers use 3.175% to 3.575% for 2019

Mining employer use 3.575% for 2019
Rates include the 0.475% fund-building factor

State Disability Insurance (SDI):

None

State labor laws:

Minimum Wage - $8.25 for 2019
Termination Pay - Fired/Quit - next regular payday

New Hire Reporting:

Employers must report hiring, rehiring, and return reporting to work within 20 days on New Hire Reporting Form to:

Illinois New Hire Directory 
P.O. Box 19473 
Springfield, IL 62794-9473
312-327-4473
217-557-1947 (fax)

Remit Withholding for Child Support to:

Illinois State Disbursement Unit
P.O. Box 5400
Carol Stream, IL 60197-5400
877-664-5738

Reciprocity States:

Iowa, Kentucky, Michigan, Wisconsin