Illinois Income Tax Rate 2025. The 2024 tax rates and thresholds for both the illinois state tax tables and federal tax tables are comprehensively integrated into the illinois tax calculator for 2024. Illinois has a 9.5 percent corporate income tax rate.
Use smartasset’s paycheck calculator to calculate your take home pay per paycheck for both salary and hourly jobs after taking into account federal, state, and local taxes. Unlike the federal tax code, which uses a progressive system to determine the rate at which income is taxed, illinois’ state income tax is a flat 4.95% across the board.