Illinois Paycheck Calculator

Illinois taxes every dollar of taxable wages at the same 4.95% — the state constitution requires a single rate — softened only by a $2,925 exemption allowance for each person in the household. This calculator applies both, alongside the federal lines.

Tax year 2026 Estimated annual liability allocated across pay periods — 2026 figures verified at the source Last reviewed:

Your pay and deductions

Pay and filing

Before tax and deductions.

Illinois allows the $2,925 exemption per person — you, a spouse on a joint return, and each dependent.

Deductions and adjustments Retirement, health, and other payroll deductions

Taken pre-tax from your pay.

Roth 401(k), garnishments, union dues — anything taken after tax.

On this page
  1. Flat by constitutional command
  2. What Illinois does not tax
  3. Worked examples
  4. No local income taxes — including Chicago
  5. Official sources
  6. Frequently asked questions
  7. Related calculators

Flat by constitutional command

Illinois cannot have tax brackets. Its constitution requires any individual income tax to be levied at a single, non-graduated rate — voters declined to change that in 2020 — so the 4.95% in force since 2017 applies to the first dollar of taxable income and the millionth alike. What varies by household is not the rate but the exemption allowance: $2,925 for 2026, claimed once per person. A married couple with two children shields $11,700 before the 4.95% starts.

The mechanics are short: Illinois starts from federal AGI, adds and subtracts a few Schedule M items, subtracts the exemptions, and multiplies. There is no standard deduction — the per-person exemption is the whole relief structure, and it phases out entirely at very high incomes (this calculator applies it in full and says so in the notes).

What Illinois does not tax

Retirement income, almost categorically: Social Security benefits, qualified 401(k) and IRA distributions, and most pensions are exempt — one of the most generous retirement carve-outs of any taxing state. Wages have no such luck. Pre-tax 401(k) deferrals, health premiums, and HSA contributions do reduce Illinois wages on the way in, the same as federal.

Worked examples

Three Illinois salaries through the 4.95% flat rate
Annual salaryIllinois tax (4.95%)Federal income taxSocial Security & MedicareTake-home per biweekly checkAnnual take-home
$50,000$2,330$3,820$3,825$1,539.41$40,025
$75,000$3,568$7,670$5,738$2,231.72$58,025
$100,000$4,805$13,170$7,650$2,860.57$74,375

Single filer, paid biweekly, no pre-tax deductions or dependents entered. Generated by the same calculation engine as the calculator above.

No local income taxes — including Chicago

Unlike Pennsylvania or Ohio, no Illinois municipality taxes earned income. A Chicago paycheck carries the same state line as a Springfield one. Employer withholding uses Booklet IL-700-T with the same 4.95% and exemption figures used here, so Illinois withholding tracks the actual liability more closely than in most states — the gap on your stub usually comes from the federal side, not the state one.

Official sources

Every figure in this calculator traces to one of these publications; nothing is estimated from third-party summaries.

Last reviewed: July 30, 2026.

Frequently asked questions

Why does my neighbor pay the same Illinois rate on triple my income?

Because the constitution requires it. Illinois may only levy a non-graduated tax, so 4.95% applies at every income. The 2020 "Fair Tax" amendment that would have allowed brackets was rejected by voters; changing the structure would take another constitutional amendment.

Does Chicago add a city income tax?

No Illinois municipality taxes earned income — Chicago included. Illinois law does not grant cities that power. Whatever the rumor before an election, a Chicago city income tax would need Springfield to authorize it first.

How much does each dependent save me in Illinois?

Each exemption shields $2,925 of income for 2026, worth $144.79 at the 4.95% rate — roughly $5.57 per biweekly paycheck. Small per check, but a family of four shields $11,700 a year, and unlike the federal exemption it still exists.

Is my 401(k) money ever taxed by Illinois?

Contributions reduce Illinois wages going in, and — unusually — qualified distributions are exempt coming out. Illinois exempts most retirement income, so a 401(k) dollar can legitimately avoid Illinois tax entirely across its life. The federal government is less forgiving on the way out.