Illinois self-employment tax at a glance
Illinois taxes all income at a flat 4.95% after a personal exemption. The state constitution requires a flat rate, so high earners pay the same percentage as everyone else. The exemption is unavailable at high income levels, which this estimate does not model.
- State income tax: a flat 4.95% income tax (top marginal rate 4.95%)
- Standard deduction / exemption: $2,850 single, $5,700 married filing jointly
- Estimated payments: Form IL-1040-ES
- Tax agency: Illinois Department of Revenue
- Local income taxes: None for most residents
How Illinois compares: take-home pay on 1099 income
The table compares a single filer with no business expenses in Illinois with the average state income tax across the15 states we cover and with a state that has no income tax. Every column includes self-employment tax and federal income tax.
| Net profit | Illinois state tax | Avg. state tax | Total tax | Illinois take-home | No-income-tax state |
|---|---|---|---|---|---|
| $50,000 | $2,159 | $1,158 | $11,891 (23.8%) | $38,109 | $40,268 |
| $75,000 | $3,309 | $2,012 | $18,804 (25.1%) | $56,196 | $59,505 |
| $100,000 | $4,459 | $2,912 | $26,824 (26.8%) | $73,176 | $77,635 |
| $150,000 | $6,759 | $4,749 | $44,367 (29.6%) | $105,633 | $112,392 |
| $250,000 | $11,502 | $8,541 | $78,456 (31.4%) | $171,544 | $183,046 |
2026 Illinois income tax brackets
| Single rate | Single taxable income | Married rate | Married filing jointly |
|---|---|---|---|
| 4.95% | Over $0 | 4.95% | Over $0 |
How this calculator works
- Net profit is your gross 1099 income minus deductible business expenses.
- Self-employment tax is 15.3% (12.4% Social Security up to the $184,500 wage base, plus 2.9% Medicare) on 92.35% of net profit.
- Federal income tax applies the 2026 brackets after subtracting half of your SE tax, the standard deduction and the 20% qualified business income (QBI) deduction.
- Illinois tax applies Illinois's brackets to your adjusted gross income after the state deduction or exemption.
- Quarterly payments divide the annual federal amount evenly.
Not included: credits, itemized deductions, retirement contributions (SEP-IRA, Solo 401(k)), self-employed health insurance deduction and local taxes. Each of these usually lowers the bill, so treat the result as a conservative upper estimate.