New Company Registration for Illinois

Tax Agency

Illinois Department of Revenue

Type of Tax

State Withholding Income Tax
Unemployment Insurance Tax (UI)
You must register with the Illinois Department of Revenue if you conduct business in Illinois, or with Illinois customers.

Registration Steps:

  1. Register for a Taxpayer ID.
    • Go to MyTaxIllinois
    • Under Register, select “Register a New Business”
    • Register for both state income tax withholding and unemployment tax
  2. Create a username and password.
    • Go back to MyTaxIllinois and select “sign up”
    • If you completed the activation summary and successfully submitted the information, you should first receive a confirmation screen and then an email, containing your authentication code, a few minutes later.
    • Activation is based on your Social Security number (SSN) if you are a sole proprietor or your Federal Employer Identification Number (FEIN) for all other businesses. This means that all the tax types under your FEIN or SSN will be in one MyTax Illinois Account.

Update your Homebase account with your Illinois Taxpayer ID. Your Illinois Taxpayer ID is required for all Illinois Department of Revenue interactions to ensure your account is accurate.
If you have any questions regarding this process, please call a customer support representative at (217) 785-3707 or email REV.DoNotReply@Illinois.gov.

Third party access to Illinois Department of Revenue

In order to file and pay Illinois taxes on your behalf, you must grant Check access to
your MyTax Illinois account

  • Login to your MyTax Illinois account
  • Click on Settings in the top-right hand menu.
  • Select Manage Third Party Access.
  • Under "Third Party Access" make sure the:
    • "Allow" setting is set to Yes.
    • "Default access" is set to Third Party.
    • "Default account access" is set to Full Access.

*Note: Homebase uses a payroll partner, Check for backend payroll processing.

Disclaimer:
This article is not intended to be tax, legal, financial, or HR advice. Rules and regulations change over time and can vary by location. Consult with a lawyer, accountant, Tax, or HR expert for specific guidance.

Last Updated 11/1/2021