Illinois pay stubs: flat 4.95% income tax and IL-W-4

State income tax

Illinois has a flat income tax of 4.95% for 2026, and the withholding math is refreshingly simple. For each paycheck, the employer subtracts the value of the allowances the employee claimed on Form IL-W-4, divided across the year's pay periods, and multiplies what is left by 4.95%. Each basic allowance is tied to the Illinois personal exemption, and there is also a separate, smaller allowance for things like age or blindness.

Because the allowance value changes from time to time, the 2026 withholding tables differ slightly from 2025's even though the rate did not change. The Illinois Department of Revenue publishes the tables each year in booklet IL-700-T.

Other state payroll deductions

Illinois does not have a state disability insurance program or a payroll-funded paid family leave program. Illinois requires paid leave for many workers, but it is paid by the employer as regular wages, not through a payroll tax on employees. Unemployment insurance is an employer tax.

Local taxes

Illinois cities and counties, including Chicago, do not tax employee wages, so there is no local income tax line on an Illinois pay stub.

Federal withholding still applies

Whatever Illinois requires, the federal deductions are the same as in every other state. Federal income tax is figured from the employee's Form W-4. Social Security takes 6.2% of wages until the employee reaches the annual Social Security wage base. Medicare takes 1.45% of every dollar, and once an employee's wages for the year pass $200,000, the employer also withholds the 0.9% Additional Medicare Tax.

Creating an Illinois pay stub with PayStubNest

Enter the hours worked and hourly rate, or an annual salary, and choose Illinois as the work state. The exact figures on each stub depend on the employee's pay, pay frequency, W-4 choices, deductions and year-to-date totals, so no two paychecks are quite alike. PayStubNest calculates all of it automatically, applying federal and Illinois withholding and carrying year-to-date totals forward from one stub to the next. You can preview a stub for free and only pay when you download it.

Record-keeping tip

Keep each employee's IL-W-4 on file and note the number of allowances claimed on the stub or in your payroll notes. When an employee questions their state withholding, that one number usually explains it. Tables and forms are at the Illinois Department of Revenue. See our FAQ too.