Illinois Paycheck Calculator 2025 — Flat 4.95% State Income Tax

Illinois Flat Tax: 4.95%

Unlike most states, Illinois uses a flat (single-rate) income tax of 4.95% on all taxable income — the same rate regardless of how much you earn. This makes estimating your Illinois tax straightforward.

Enter Your Gross Pay

Gross Pay ($)

Pay Frequency

Filing Status

401(k) Contribution (%)

Your Illinois Paycheck Breakdown

Gross Pay

—

Total Deductions

—

Net Take-Home

—

Gross Pay —

Federal Income Tax —

Social Security (6.2%) —

Medicare (1.45%) —

Illinois State Tax (4.95% flat) —

401(k) Contribution —

Net Take-Home Pay —

Note: Illinois allows a personal exemption of $2,425 per filer (2024). This calculator applies that exemption. Chicago and some other IL municipalities levy additional local income taxes not shown here.

Illinois Tax Summary

Federal Income Tax	10% – 37% (progressive brackets)
Social Security	6.2% (up to $168,600 wage base)
Medicare	1.45% (+ 0.9% over $200k)
IL State Income Tax	4.95% flat rate
IL Personal Exemption	$2,425 per filer

Tax rates shown are based on the latest available data but may not reflect the most recent legislative changes. Always verify current rates at your state's official revenue department website before making financial decisions.