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🦅 Illinois Income Tax Calculator
Illinois has a constitutionally mandated flat income tax of 4.95%, though it also has high property taxes.
Uses 2025 tax-year brackets
Illinois State Tax Facts (2025 tax year)
Constitutionally flat 4.95% income tax
One of the highest property tax burdens in the nation
Chicago residents pay an additional city income tax
4.95%
Top state rate
On top of federal income tax, Illinois residents pay up to 4.95% in state income tax. Use the calculator above to see your combined effective rate.
Frequently Asked Questions
What is the income tax rate in Illinois?+
How do I calculate my take-home pay in Illinois?+
Filing Taxes in Illinois: What the Rate Table Doesn't Tell You
How filing works here
Illinois levies a flat 4.95% income tax, and the flatness is locked into the state constitution — voters rejected a graduated-rate amendment in 2020, so the single rate applies to all taxable income. You file Form IL-1040. The flat rate makes Illinois unusually simple to estimate: your state tax is essentially 4.95% of your Illinois base income, with few moving parts.
The local quirk to know
Illinois fully exempts retirement income from state tax — pensions, 401(k) and IRA distributions, and Social Security are all excluded. That makes Illinois one of the most tax-friendly states in the country for retirees, a fact that surprises people who only know its reputation for high property taxes. On the other side of the ledger, Illinois property taxes are consistently among the highest in the nation in effective terms, and they are the main offset to the flat income-tax rate.
Planning note
Because the rate is flat, there is no bracket-management strategy in Illinois — timing income across years does not change the rate the way it does in progressive states. Planning here is about the base, not the rate: maximizing pre-tax retirement contributions and, for business owners, entity-structure choices that affect what counts as Illinois base income. And if you own a home, appeal your property-tax assessment regularly; Cook County's assessment system in particular produces frequent over-assessments that go unchallenged.
Written by Alex Chen. Tax rules change — confirm current-year figures with the IRS before filing.
Go Beyond Tax — Plan Your Full Financial Picture
Your Illinois take-home pay is the starting point. Map every dollar in a monthly budget and see how your savings compound over time.
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