Illinois Self-Employment Tax Calculator 2026
Estimate self-employment tax, federal and Illinois income tax and quarterly payments on LLC, sole proprietor and 1099 income in Illinois.
Total tax on your profit
$26,820
Pay about $6,705 each quarter in estimated tax · you keep $73,180
Self-employment tax
$14,130
Effective rate
26.8%
QBI deduction
$15,367
- Kept 73.2%
- SE tax 14.1%
- Federal 8.2%
- State 4.5%
| Quarter | Year | |
|---|---|---|
| Net business profit | $25,000.00 | $100,000 |
| Self-employment tax (15.3%) | −$3,532.39 | −$14,130 |
| Federal income tax | −$2,058.75 | −$8,235 |
| Illinois income tax | −$1,113.88 | −$4,456 |
| Left after tax | $18,294.99 | $73,180 |
Quick answer: With $100,000 of net profit in Illinois, a single business owner pays about $26,820 in total tax for 2026 (26.8%), including $14,130 of self-employment tax. Budget about $6,705 for each quarterly estimated payment.
Illinois self-employment tax by profit (2026)
| Net profit | SE tax | Federal tax | IL tax | Total tax | Effective rate | Per quarter |
|---|---|---|---|---|---|---|
| $25,000 | $3,532 | $571 | $1,005 | $5,108 | 20.4% | $1,277 |
| $50,000 | $7,065 | $2,667 | $2,155 | $11,887 | 23.8% | $2,972 |
| $75,000 | $10,597 | $4,898 | $3,305 | $18,800 | 25.1% | $4,700 |
| $100,000 | $14,130 | $8,235 | $4,456 | $26,820 | 26.8% | $6,705 |
| $150,000 | $21,194 | $16,413 | $6,756 | $44,363 | 29.6% | $11,091 |
| $200,000 | $28,234 | $25,196 | $9,056 | $62,487 | 31.2% | $15,622 |
| $300,000 | $31,606 | $60,643 | $13,940 | $106,189 | 35.4% | $26,547 |
| $500,000 | $38,625 | $131,787 | $23,708 | $194,119 | 38.8% | $48,530 |
Single filer, standard deduction, 20% QBI deduction (phased out for service businesses above $201,750), no other income.
How self-employment income is taxed
As a sole proprietor, independent contractor or single-member LLC owner, you pay three taxes on your net profit. Self-employment tax of 15.3% covers Social Security and Medicare, both the employee and employer halves. Federal income tax applies to profit after half of your SE tax, the standard deduction and the 20% qualified business income (QBI) deduction. Illinois income tax applies to the same profit: the state has a flat income tax of 4.95%. Single filers claim a $2,925 personal exemption.
Nobody withholds these taxes for you, so the IRS and Illinois expect quarterly estimated payments if you'll owe $1,000 or more for the year.
Illinois business taxes and fees beyond income tax
LLC fees: forming an LLC in Illinois costs $150. Ongoing: $75 annual report.
Other business taxes: Personal property replacement tax (2.5% corporations, 1.5% partnerships and S corps); franchise tax on paid-in capital with first $10,000 exempt.
Read the full Illinois business tax guide or compare LLC fees in every state.
Illinois vs. nearby states: tax on $100,000 of profit
Frequently Asked Questions
How much tax do I pay on $100,000 of self-employment income in Illinois?
A single sole proprietor or single-member LLC owner with $100,000 of profit in Illinois owes about $26,820 in 2026: $14,130 of self-employment tax, $8,235 of federal income tax and $4,456 of state income tax. That's 26.8% of profit, or about $6,705 a quarter in estimated payments.
How much should I set aside for taxes as a self-employed person in Illinois?
At $100,000 of profit, set aside about 30% of every payment you receive. At lower profits the share is smaller and at higher profits it's larger; use the table on this page to find your level.
What is the self-employment tax rate in Illinois?
Self-employment tax is federal, so it's the same in every state: 15.3% on 92.35% of your net profit, made up of 12.4% Social Security on the first $184,500 and 2.9% Medicare on everything. An extra 0.9% Medicare tax applies above $200,000 ($250,000 for married couples). You can deduct half of it from your income.
Does Illinois tax LLC income?
Yes. A single-member LLC's profit passes through to your Illinois personal return. Illinois has a flat income tax of 4.95%. LLC fees in Illinois: $75 annual report.
When are quarterly estimated taxes due?
For 2026, federal estimated payments are due April 15, June 15 and September 15, 2026, and January 15, 2027. Most states with an income tax use the same dates. Paying at least 100% of last year's tax (110% if your income was over $150,000) avoids an underpayment penalty.
Would an S corporation lower my self-employment tax?
Possibly, once profit is high enough. An S corporation owner pays payroll tax only on a reasonable salary, not on the rest of the profit. Above roughly $60,000 to $80,000 of profit, the saving often covers the extra payroll and filing costs. Our guides to LLC and corporation taxes walk through the trade-offs.
Illinois Paycheck Calculator →
Take-home pay per paycheck after federal, state and payroll taxes.
Illinois Tax Brackets →
2026 income tax brackets, standard deductions and exemptions for single and married filers.
Illinois business tax guide →
Corporate tax, sales tax, LLC fees and more.
Self-employment tax calculators for other states
Sources
- https://www.irs.gov/pub/irs-drop/rp-25-32.pdf
- https://www.ssa.gov/oact/cola/cbb.html
- https://taxfoundation.org/data/all/state/state-income-tax-rates-2026/
- https://www.irs.gov/businesses/small-businesses-self-employed/self-employment-tax-social-security-and-medicare-taxes
- https://tax.illinois.gov/research/taxrates/income.html
- https://www.ilsos.gov/departments/business_services/
Estimates use 2026 federal and state rates and standard deductions, and assume no other income, itemized deductions or credits beyond those listed. Your employer's withholding may differ from your final tax bill. For informational purposes only; this is not tax advice.