How your paycheck is taxed in Illinois
A Illinois paycheck is reduced by federal income tax, Social Security (6.2%), Medicare (1.45%), and a flat 4.95% state income tax. The federal side uses the 2026 standard deduction of $16,100 (single) or $32,200 (joint) and seven brackets from 10% to 37%. The state side is described below. The 2026 exemption will be slightly higher after inflation indexing.
Formula
Net pay = Gross pay - Pre-tax deductions - Federal income tax - Social Security - Medicare - Illinois income tax - After-tax deductions. Federal taxable income is gross minus pre-tax deductions minus the standard deduction. Illinois taxable income is wages minus the personal exemption.
Illinois income tax rate for 2026
| Item | Amount |
|---|---|
| Tax rate (all filing statuses) | 4.95% |
| Personal exemption, single | $2,850 |
| Personal exemption, married filing jointly | $5,700 |
Illinois has taxed income at a flat 4.95% since 2017. There is no standard deduction, only a personal exemption ($2,850 per person for 2025).
Worked examples: single filer, paid biweekly
Each row is a single filer with no pre-tax deductions, using the 2026 federal tables and the Illinois rules above. The $75,000 example: federal taxable income is $58,900 after the $16,100 standard deduction, giving $7,670.00 of federal tax (10% on the first $12,400, 12% up to $50,400, 22% on the rest). Social Security is 6.2% of $75,000 = $4,650.00, Medicare is 1.45% = $1,087.50, and Illinois tax on $72,150 of state taxable income is $3,571.43. Net pay is $58,021.08 a year, or $2,231.58 every two weeks.
| Salary | Federal tax | Social Security | Medicare | Illinois tax | Net per year | Net per paycheck |
|---|---|---|---|---|---|---|
| $50,000 | $3,820 | $3,100 | $725 | $2,334 | $40,021 | $1,539.27 |
| $75,000 | $7,670 | $4,650 | $1,088 | $3,571 | $58,021 | $2,231.58 |
| $100,000 | $13,170 | $6,200 | $1,450 | $4,809 | $74,371 | $2,860.43 |
Effective total tax rates in these examples run from 20% at $50,000 to 25.6% at $100,000. Married filers with the same household income pay less federal tax because the joint standard deduction and brackets are twice as wide.
How a flat tax changes with income
Because every dollar of taxable income is taxed at 4.95%, Illinois tax rises in a straight line once you are past the deduction and exemption. In the examples above it is $2,334 at $50,000 (4.67% of gross), $3,571 at $75,000 (4.76%), and $4,809 at $100,000 (4.81%). The federal side is what makes the total effective rate climb faster than that, since federal brackets step from 12% to 22% at $50,400 of taxable income and to 24% at $105,700.
Hourly pay in Illinois
Hourly workers are annualized the same way: rate x hours per week x 52. At $20 an hour for 40 hours, gross pay is $41,600 a year or $800 a week. Federal income tax is $54.08 a week, Social Security $49.60, Medicare $11.60, and Illinois tax $36.89, leaving $647.84 per weekly paycheck. Overtime raises the annualized figure and can push a few dollars into the next federal bracket, but only those dollars are taxed at the higher rate.
Married filing jointly on $75,000
A married couple filing jointly with $75,000 of combined wages gets the $32,200 joint standard deduction and brackets twice as wide, so federal income tax falls to $4,640.00 from $7,670.00 for a single filer, and Illinois tax is $3,430.35 instead of $3,571.43. Social Security and Medicare do not change with filing status. Take-home pay for the couple is $61,192.15 a year, or $2,353.54 per biweekly paycheck.
Estimates for 2026 using federal and state tables; local taxes, benefits, and credits vary. Not tax advice. Compare other states on the national paycheck calculator.