Il Income Tax Rate 2025. The illinois tax calculator is for the 2025 tax year which means you can use it for estimating your 2026 tax return in illinois, the calculator allows you to calculate income tax and payroll taxes. The tax tables below include the tax rates, thresholds and allowances included in the illinois tax calculator 2025.
No illinois cities charge a local income tax on top of the state income. Illinois has a flat income tax of 4.95%, which means everyone’s income in illinois is taxed at the same rate by the state.