Register in Illinois

Illinois Tax Agencies

  • Illinois Department of Revenue - income tax withholding
  • Illinois Department of Employment Security (IDES) - unemployment tax

Set up an existing company

The Department of Revenue issues you an income tax withholding taxpayer ID. This taxpayer ID number will include your FEIN and Sequence number, and you can find it on your Illinois Withholding Income Tax Return (IL-941). If you are unsure about your taxpayer ID number (especially the sequence number), please contact (800) 732-8866.

Your Unemployment account number and your Illinois UI Contribution Rate will be on the Notice of Contribution Rate that you receive from the Illinois Department of Employment Security (IDES) each year. Please note your unemployment tax number is NOT the same as your FEIN. It ranges from 0.55% to 7.35%, with a wage base of $12,960. When entering your UI Contribution Rate, please be sure to include the Fund Builder Rate of 0.55%. If you're unsure about your rate, please call the agency at (800)247-4984.

Register a new company

Income tax withholding and unemployment tax

  1. Register for both income tax withholding and unemployment tax through the Illinois Department of Revenue website. Click registration and complete.
  2. For Income Tax Withholding, you’ll receive a taxpayer ID which will consist of your Federal EIN plus a Sequence Number (-XXX). You will be required to fill out the sequence number in Gusto to ensure payments are properly paid. If you are unsure about your sequence number, please reach out to the department at (800) 732-8866.
  3. For Unemployment Tax, most companies are liable for state unemployment if they pay at least $1,500 in wages in a single calendar quarter or employed one or more persons for 20 weeks in a given calendar year. If considered liable, you'll instantly be issued an Unemployment Account Number in the format of XXXXXXX-X. The last digit of your Unemployment number is called the check digit and the department will often omit it from correspondence. Gusto does not require the final digit when entering the number in your account. 
  4. UI tax rate: The unemployment rate for new employers varies by industry, but is generally between 3.45%-3.65%, which includes the .55% Fund Builder Rate.


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