ποΈ Illinois Income Tax Calculator
The flat 4.95% rate, exemptions applied.
Estimated Illinois income tax
Estimates for planning only, not financial advice.
Illinois taxes income at a single flat rate of 4.95%, no brackets, no standard deduction. You start with federal adjusted gross income, subtract Illinois exemptions of $2,925 per person for 2026, subtract qualifying retirement income, and multiply what is left by 4.95%. A single filer earning $75,000 with one exemption owes about $3,567.71, an effective rate of 4.76% once the exemption does its small work.
How to Use This Calculator
Enter your federal AGI from your 1040, the number of exemptions (1 for single, 2 for married filing jointly, plus dependents), and any retirement income that Illinois excludes. The calculator returns your Illinois base income and the tax.
Enter federal AGI. Illinois starts where the federal return leaves off, then applies its own additions and subtractions.
Enter exemptions: one per filer plus one per dependent. At $2,925 each for 2026, they are small but real.
Enter retirement income (Social Security, pensions, 401(k) and IRA distributions) that Illinois fully excludes, and read your estimated tax. For the federal half of the return, see our federal income tax calculator.
The Illinois Tax Formula
The flat rate is the whole story, which is both the appeal and the complaint. Everyone from a barista to a CEO faces the same 4.95% on taxable income. There is no standard deduction, so the $2,925 exemption is the only universal break, and it phases out entirely once AGI passes $250,000 for most filers ($500,000 joint). Illinois voters rejected a graduated-rate constitutional amendment in 2020, so the flat structure is locked in by the state constitution.
Worked Example
Single filer, $75,000 federal AGI, one exemption, no retirement income. Subtract the $2,925 exemption to get Illinois base income of $72,075.00. Multiply by 4.95%: tax is $3,567.71. Now add a twist: a retiree couple with $60,000 of pension income and nothing else. Illinois excludes all of it, base income is $0, tax is $0. That exclusion is one of the most generous retirement breaks in the country and a genuine reason retirees stay in Illinois despite the property taxes.
What Illinois Does Differently
Three things stand out. First, the retirement exclusion covers Social Security, pensions, and 401(k)/IRA distributions completely. Few states go that far. Second, there is a 5% property tax credit on taxes paid for your primary residence, which softens the country's second-highest property tax burden just slightly. Third, Illinois has no local income tax, so Chicago workers pay the state flat rate plus federal tax and stop there. The tradeoff is visible in the other direction: sales taxes in the Chicago area run above 10% combined, and property taxes are brutal.
My read: Illinois is cheap to earn in and expensive to own in. If you rent and work, the flat 4.95% with the retirement exclusion is straightforward and often lower than it looks. If you own a home, run the property tax credit math carefully, because the income tax is the smaller half of your state burden. Chicago-area workers should also check overtime rules with our Illinois overtime calculator before assuming a salary is fair.
Estimates for planning only, not financial advice.
Frequently Asked Questions
What is the Illinois income tax rate for 2026?
A flat 4.95% on Illinois taxable income, unchanged since July 2017. The rate applies equally to all income levels and filing statuses. The personal exemption for 2026 is $2,925 per person, up from $2,850 in 2025 through an inflation adjustment.
How is Illinois taxable income calculated?
Start with federal adjusted gross income, add Illinois-specific additions like out-of-state bond interest, then subtract Illinois subtractions. The big ones: the $2,925-per-person exemption allowance and the full exclusion of qualifying retirement income. Multiply the result by 4.95%.
Does Illinois tax Social Security benefits?
No. Illinois excludes Social Security, pension income, 401(k) distributions, and IRA withdrawals from state tax entirely. It is one of only a handful of states with a blanket retirement income exclusion, and it survived every recent reform attempt.
Is there a standard deduction in Illinois?
No. Illinois has no standard deduction. The exemption allowance of $2,925 per person is the closest equivalent, and it is much smaller than the federal standard deduction. Do not subtract the federal standard deduction again on the state return.
Do I lose the exemption at high incomes?
Yes. The exemption allowance is disallowed when AGI exceeds $500,000 for joint filers or $250,000 for all other filing statuses. Above those lines, the full 4.95% applies to every dollar of base income.
Does Chicago add a local income tax?
No. Illinois cities and counties cannot levy an income tax. Chicago collects plenty of other taxes, including high sales taxes and fees, but your paycheck faces only the state 4.95% plus federal tax.
What is the Illinois property tax credit?
A 5% credit against your Illinois income tax for property taxes paid on your principal residence. On a $10,000 property tax bill, that is a $500 credit. It is nonrefundable, so it cannot take tax below zero, but it takes real money off the bill.
When is the Illinois return due?
April 15 for calendar-year filers, matching the federal deadline. Illinois Form IL-1040 is short because the computation is short: base income, exemptions, one multiplication. Estimated payments follow the federal quarterly schedule.
Can Illinois raise the flat rate?
Yes, the legislature can raise it, but the state constitution requires a single flat rate for all taxpayers, so any increase hits every bracket equally. That constitutional rule is why the 2020 graduated-tax amendment failed at the ballot box.
Do nonresidents working in Illinois owe the tax?
Yes, on Illinois-source income. Work physically performed in Illinois is taxable there even if you live elsewhere, with a credit on your home state return to avoid double taxation in most cases. Remote workers should check both states' rules.