Results are estimates for educational purposes only. Based on 2026 IRS federal brackets and Illinois state tax rates. Always consult a qualified tax professional.
Illinois income tax overview
Illinois has a flat state income tax rate of 4.95% on all taxable income — the same rate regardless of whether you earn $30,000 or $3 million. Illinois is one of nine states using a flat tax system. The state also has a personal exemption of $2,425 per person and exempts Social Security benefits from state tax. Illinois has been under financial pressure for years due to pension obligations, and there have been repeated political discussions about switching to a graduated income tax — a 2020 ballot measure to do so was rejected by voters. Chicago residents pay an additional city tax through higher property and sales taxes but no local income tax.
2026 Illinois income tax rates
Tax rate
Income range (single filer)
4.95% flat
All taxable income
Worked example: $75,000 salary in Illinois
A $75,000 salary in Illinois results in approximately $3,584 in state income tax (4.95% flat rate after personal exemption), plus $12,580 federal tax, $4,650 Social Security, and $1,088 Medicare. Annual take-home is approximately $53,098, or $2,042 bi-weekly.
Key facts: 4.95% flat rate · Social Security exempt · Retirement income exempt
Frequently asked questions — Illinois income tax
The Illinois Constitution requires that any income tax be uniform — the same rate on all income. This effectively mandates a flat tax system. Changing to a graduated system would require a constitutional amendment, which Illinois voters rejected in November 2020.
No. Illinois does not tax Social Security benefits, retirement income from qualified plans (401k, IRA, pension), or military pay. This makes Illinois more retirement-friendly than many states despite its higher overall tax burden.
Illinois cities and counties do not levy local income taxes. However, Chicago has high property taxes and a 1.25% city sales tax on top of state and county sales taxes. The combined sales tax in Chicago reaches 10.25%.
Illinois allows a personal exemption of $2,425 per taxpayer (and per dependent) in 2026. This reduces your taxable income before the 4.95% rate is applied.
Illinois at 4.95% flat is higher than Indiana (3.05% flat) and Michigan (4.25% flat), but lower than Wisconsin (top rate 7.65%) and Minnesota (top rate 9.85%). Missouri's top rate is 4.8%, making it slightly lower than Illinois.
Compare Illinois to other states
Use our US income tax calculator to compare your take-home pay across all 50 states. You may be surprised how much location affects your net income.