Illinois charges 4.95% flat state income tax. Use the self-employment tax calculator pre-loaded with Illinois rates.
Open Self-Employment Tax Calculator →Freelancing in Illinois means stacking a flat 4.95% state income tax on top of the 15.3% self-employment tax and federal income tax. The combined marginal rate for freelancers here can exceed 42% on income in the 22% federal bracket. Careful quarterly estimated payment planning is critical to avoid underpayment penalties. This calculator factors in Illinois's state tax and the deductible half of SE tax to give you an accurate picture.
Illinois levies a flat 4.95% state income tax on all taxable income regardless of how much you earn. This makes tax planning straightforward: for every additional dollar you earn, 4.95 cents goes to Illinois. Illinois does not impose local income taxes, so the 4.95% flat rate is the only state-level income tax you owe.
The table below shows what you actually keep at five salary levels in Illinois, accounting for federal tax, FICA, and Illinois's flat 4.95% state tax.
See how Illinois compares to other Midwest states. Each link takes you to the self-employment tax calculator landing page for that state.
For a comprehensive breakdown of Illinois’s tax structure, salary comparisons, cost-of-living analysis, and more, visit the full Illinois take-home pay page.