How to Calculate Illinois Income Tax Withholdings

Paying employees accurately and on time is very important for any business. Usually you can calculate Illinois payroll income tax withholdings in the following ways.

Calculate Illinois state tax manually by using the state tax tables

Use payroll software to automate the tax calculations

Hire an accountant

Option 1: Calculate Illinois State Income Tax Manually

If you like to calcualte state tax withholdings manually, you can refer to the Illinois tax tables and step by step guide there.

If you need to create the paychecks and paystubs by entering the federal and state tax amount, you can refer to this article How to Generate After the Fact Paychecks with Stubs

Option 2: Payroll Software Saves IL Businesses Time and Money by Calculating the Taxes Automatically

EzPaycheck Payroll software is a good choice for many small business employers. Once you set up company and employee, ezPaycheck will calculate Illinois income tax for you automatically. Here are the quick guide.

ezPaycheck Makes Payroll An Easy, In-House Task!

(For Windows and Mac)

Trusted by Thousands for Two decades.

Calculate Federal & State Taxes, Print Paychecks, Print W2, W3, 941, 943 and 940.

User-friendly, Easy-to-use

No monthly fee.

ezPaycheck 2025 is shipping!

Try it free for 30 days with no obligation. No credit card required.

Step 1: Download and install ezPaycheck payroll software

We have ezPaycheck 2008 to current available from our site. Please choose the right version to download. For example: If you need to calculate Year 2025 income tax, please download ezPaycheck 2025.

Step 2: Set up Company

Select the rigth Pay Period Start ezPaycheck application, click the left menu "Company Settings" then click the sub menu "Company" to open the company setup screen. Please make sure you select the correct Pay Period there.

(Click image to enlarge)

Set up company tax information option

You can click the left menu "Company Settings" then click the sub menu "Tax Information" to open the company tax setup screen

Step 3: Set up Employee Profile

Enter employee address correctly

Start ezPaycheck application, click the left menu "Employees" then click the sub menu "Add Employee" to add employee profile. EzPaycheck calculates state tax based on employee address.

Enter the tax option for this employees

Step 4: Add and Print a check

You can click the "ADD" button above check list on the main screen to add a new check. Or you can click the ezPaycheck payroll software left menu "Checks" then click the sub menu "New Check" to open New Check screen.
new payroll check

Print paychecks

You can select one or multiple paychecks from list and click the Print button to print paychecks together.