Illinois Paycheck Calculator
Estimate your Illinois take-home pay after federal tax, FICA, and Illinois state income tax. Enter your gross pay, filing status, and pre-tax deductions to see your net pay per paycheck.
2026 rate, standard deduction, and personal exemption verified against Tax Foundation 2026 data.
- Take-home$51,334.79 · 78.98%
- Federal tax$5,620.00 · 8.65%
- Social Security + Medicare$4,972.50 · 7.65%
- Illinois tax$3,072.71 · 4.73%
| Item | Per bi-week | % of gross |
|---|---|---|
| Gross pay | $2,500.00 | 100% |
| Federal withholding | $216.15 | 8.65% |
| Social Security | $155.00 | 6.20% |
| Medicare | $36.25 | 1.45% |
| Illinois income tax | $118.18 | 4.73% |
| Take-home pay | $1,974.41 | 78.98% |
Illinois cannot have brackets, by constitution
Illinois charges a flat 4.95% on taxable income, and unlike most flat-tax states this is not a policy choice that could be reversed by ordinary legislation. The Illinois constitution requires a non-graduated income tax. A 2020 ballot amendment to permit graduated rates was put to voters and failed, so the flat structure remains constitutionally entrenched.
For anyone planning long term, that is unusual certainty. The rate can move, but the shape cannot without another constitutional amendment.
Illinois does not tax retirement income
This is the single most consequential fact about Illinois personal income tax, and it rarely appears in paycheck guides because it does not affect your pay stub. Illinois excludes qualified retirement income — pension payments, 401(k) and IRA distributions, and Social Security benefits — from state taxable income entirely.
The effect on your working years is indirect but real: a dollar deferred into a traditional 401(k) escapes the 4.95% now, and is still not taxed by Illinois when withdrawn. In most states, pre-tax deferral only postpones the state tax. In Illinois, for a worker who retires in state, it can avoid it permanently.
Exemptions instead of a standard deduction
Illinois has no standard deduction. It applies a personal exemption per filer and dependent, which is modest relative to the deductions in states like Colorado or Idaho, so a larger share of your income faces the 4.95% than the rate alone implies.
Alongside that, your paycheck carries federal income tax, Social Security to the wage cap, and Medicare with the high-earner surcharge. Illinois levies no local income tax on wages and no employee payroll programme premium.
Making the retirement exclusion work for you
If you expect to retire in Illinois, the state's treatment of retirement income makes traditional pre-tax contributions unusually attractive compared with Roth. You take the 4.95% deduction on the way in and Illinois does not tax the withdrawal on the way out.
If you expect to retire elsewhere, that advantage does not travel — the destination state's rules will apply to your distributions. The calculator above handles the working-year half of this; the retirement half depends on where you end up.
How Illinois taxes your paycheck
Illinois has a flat 4.95% state income tax. Use the calculator above to estimate your take-home pay after all withholdings.
Every US paycheck also has federal income tax, Social Security (6.2% up to the annual wage base), and Medicare (1.45%, plus 0.9% on high earners) withheld. Your taxable income is your gross pay minus pre-tax deductions such as 401(k) and pre-tax health premiums.
Frequently Asked Questions
How much is taken out of a paycheck in Illinois?
Illinois paychecks have federal income tax, Social Security (6.2%), and Medicare (1.45%) withheld, plus a flat 4.95% state income tax. The exact amount depends on your pay, filing status, and pre-tax deductions.
Does Illinois have a state income tax?
Yes. Illinois levies a flat 4.95% state income tax in addition to federal taxes.
How is this take-home estimate calculated?
It applies 2026 estimated federal brackets, FICA rates, state income-tax rates, local taxes where configured, and employee payroll-program rates to your annual pay minus pre-tax deductions, then divides by your pay frequency. It is a simplified estimate, not official payroll withholding.
Why can't Illinois have graduated tax brackets?
The Illinois constitution requires a non-graduated income tax. A 2020 ballot amendment to permit graduated rates was put to voters and failed, so the flat structure cannot change without another constitutional amendment.
Does Illinois tax retirement income?
No. Illinois excludes qualified retirement income — pensions, 401(k) and IRA distributions, and Social Security — from state taxable income. For someone retiring in Illinois, a traditional pre-tax contribution can avoid the 4.95% permanently rather than merely postponing it.
Does Illinois have a standard deduction?
No. Illinois applies a personal exemption per filer and dependent instead, which is modest against the 4.95% rate, so a larger share of income is taxed than the rate alone suggests.