Illinois registration and tax info

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

Register for both income tax withholding and unemployment tax through the Illinois Department of Revenue website.

1. Head to the Illinois Department of Revenue website.
2. Scroll to the "Register" tile and click Register a New Business (Form REG-1).
3. Click Next once you've added some basic business information, which includes:
   • Organization type
   • FEIN (Federal Employer Identification Number)
   • Legal name
   • DBA (doing business as) name if applicable

What to expect for income tax withholding

Once you've registered, you’ll receive a Taxpayer ID which will consist of your FEIN plus a Sequence Number—you'll need to enter the correct Sequence Number in Gusto. Instructions for where to enter tax information in Gusto can be found below in this article.

• Usually this is"-000", but can sometimes be "-001".
  • Most new employers in Illinois will have the "-000" Sequence Number.
• If you're unsure about your Sequence Number, call the agency at (800) 732-8866.

What to expect for unemployment tax

Most companies become liable for state unemployment insurance tax once the company has:

• Paid $1500 in wages during a calendar quarter or;
• Had at least one Illinois-employee working for any part of the week, for 20 or more different weeks during a calendar year.

If considered liable, you'll instantly be issued an:

• Unemployment Account Number in the format of XXXXXXX-X.
  • Heads up: the last digit of your Unemployment number is called the "check digit" and the department will often omit it from correspondence.
    • Gusto only requires the first 7 digits of the Unemployment Account Number—do not include the eighth digit (if present) when entering the number in your account. Instructions for where to enter tax information in Gusto can be found below in this article.
• Unemployment "new employer" tax rate.
  • This varies by industry and includes an additional "Fund Builder Rate" which you'll need to include in Gusto. Instructions for where to enter tax information in Gusto can be found below in this article.

Monthly wage reporting requirement—Illinois Department of Employment Security

Employers with more than 25 employees in Illinois are required to file monthly wage reports to the Illinois Department of Employment Security. Gusto files this monthly report on behalf of all of our customers, regardless of the number of employees you have.

Running payroll in Gusto before you're liable for unemployment tax

If you need to run payroll and do not yet meet the requirements above, Gusto allows it. We just suggest you add the “New employer SUI tax rate” specific to Illinois in the meantime—you can find the new employer rates for each state in this article, along with instructions on how to update the rate once you become liable and receive your company-specific agency assigned rate.

Enter the tax account information in Gusto

Once a valid Illinois work address has been added in Gusto for one or more employee(s), you can add your tax account information:

1. Click the Taxes & compliance section and select Tax setup.
2. Scroll to the "Illinois Tax Setup" headline and select Manage taxes.
3. Enter your withholding Taxpayer ID and Sequence Number and Save.
   • Usually this is"-000", but can sometimes be "-001".
     • Most new employers in Illinois will have the "-000" Sequence Number.
   • If you're unsure about your Sequence Number, call the agency at (800) 732-8866.
   • If you need to update your account number for any reason: contact us from the Help or Priority support section of your account—there may be tax implications if taxes have already been paid or filed to an incorrect account number.
4. Enter your Unemployment Account Number—Gusto only requires the first 7 digits of the number, do not include the 8th digit (if present) .
   • If the account number is less than 7 digits, add leading zeros to create a seven digit number.
     • New employers will always have 7-digit numbers, and they will typically start with a "5."
5. Enter your unemployment (experience) tax rate and include the "Fund Builder Rate".
   • If you're not sure what your rate is, contact the agency at (800) 247-4984.
   • Don't have your rate yet? Check out this article and enter the new employer rate specific to the state in the meantime. Update the rate as soon as you've received your agency-assigned rate.

Third-party authorization is required for the below agency:

• Illinois Department of Revenue (DOR)

IL DOR TPA—payments and filings

You must grant Gusto access to your MyTax Illinois account in order for us to file and pay your Illinois withholding taxes. 

1. Log in to your MyTax Illinois account. 
2. Select Manage my Profile.
3. Click More....
4. In the section titled "Access", select Manage Third Party Access.
   • From here, you can indicate that you'd like to allow third party access. You'll also see which third parties currently have access to your account.
5. 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. 

To change these settings, click the blue link to toggle to the designations above.

Withholding Taxpayer ID

If you've run payroll in Illinois previously, you can find your Taxpayer ID:

• On your Illinois Withholding Income Tax Return (IL-941) or;
• By calling the agency at (800) 732-8866.

Your Taxpayer ID will consist of your FEIN plus a Sequence Number—you'll need to enter the correct Sequence Number in Gusto.

• Usually the Sequence Number is"-000", but can sometimes be "-001".
  • Most new employers in Illinois will have the "-000" Sequence Number.

If you're not sure of your Taxpayer ID or Sequence Number, call the agency at (800) 732-8866.

Unemployment Account Number and tax rate

Your Illinois Unemployment Account number and unemployment tax rate can be found on the "Notice of Contribution Rate" that you receive from the Illinois Department of Employment Security (IDES) each year. You can also sign in to your online account to find the information.

Entering your Unemployment Account Number 

Gusto only requires the first 7 digits of the number, do not include the 8th digit (if present). 

• If the account number is less than 7 digits, add leading zeros to create a seven digit number.
  • New employers will always have 7-digit numbers, and they will typically start with a "5."

Entering your unemployment (experience) tax rate

Enter both your experience rate and the "Fund Builder Rate" as the total tax rate in Gusto.

• If you're not sure what your rate is, contact the agency at (800) 247-4984.
• Don't have an agency-assigned UI rate yet? You can add the "New employer SUI tax rate" specific to Illinois in Gusto for the meantime—find the new employer rates for each state in the linked article, along with instructions on how to update the rate once you've received your company-specific rate.

Third-party authorization is required for the below agency:

• Illinois Department of Revenue (DOR)

IL DOR TPA—payments and filings

You must grant Gusto access to your MyTax Illinois account in order for us to file and pay your Illinois withholding taxes. 

1. Log in to your MyTax Illinois account. 
2. Select Manage my Profile.
3. Click More....
4. In the section titled "Access", select Manage Third Party Access.
   • From here, you can indicate that you'd like to allow third party access. You'll also see which third parties currently have access to your account.
5. 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. 

To change these settings, click the blue link to toggle to the designations above.

Once a valid Illinois address has been added in Gusto for one or more employee(s), you can add your tax account information:

1. Click the Taxes & compliance section and select Tax setup.
2. Scroll to the "Illinois Tax Setup" headline and select Manage taxes.
3. Enter your withholding Taxpayer ID and Sequence Number and Save.
   • Usually this is"-000", but can sometimes be "-001".
     • Most new employers in Illinois will have the "-000" Sequence Number.
   • If you're unsure about your Sequence Number, call the agency at (800) 732-8866.
   • If you need to update your account number for any reason: contact us from the Help section of your account—there may be tax implications if taxes have already been paid or filed to an incorrect account number.
4. Enter your Unemployment Account Number—Gusto only requires the first 7 digits of the number, do not include the 8th digit (if present) .
   • If the account number is less than 7 digits, add leading zeros to create a seven digit number.
     • New employers will always have 7-digit numbers, and they will typically start with a "5."
5. Enter your unemployment (experience) tax rate and include the "Fund Builder Rate".
   • If you're not sure what your rate is, contact the agency at (800) 247-4984.
   • Don't have your rate yet? Check out this article and enter the new employer rate specific to the state in the meantime. Update the rate as soon as you've received your agency-assigned rate.