Self-Employment Tax in Illinois (2026)
Freelancing in Illinois? You'll owe the 15.3% federal self-employment tax plus federal income tax, plus Illinois's income tax (flat 4.95%). Here's how it breaks down.
Federal self-employment tax (the same in every state)
No matter where you live, self-employment income is hit with 15.3% SE tax — 12.4% for Social Security (up to the annual wage base) and 2.9% for Medicare — on 92.35% of your net profit. You also pay federal income tax at your marginal rate. Half of the SE tax is deductible. See exactly how it's calculated in our self-employment tax guide.
Illinois state income tax on freelance income
Illinois charges a flat 4.95% state income tax on your net earnings. This state tax stacks on top of the federal SE and income tax, so budget for all three.
State rates shown are approximate for 2026 — several states are phasing rates up or down, so confirm the current rate with the Illinois Department of Revenue.
Estimate what you owe. The Self-Employment Tax Calculator computes your federal SE tax and income tax exactly, and lets you add Illinois's state rate to see your total set-aside and quarterly payments.
How much to set aside in Illinois
Plan on roughly 30–35% of your net profit for taxes as a freelancer in Illinois, then confirm your real number with the calculator. Move that percentage into a separate account every time a client pays you, and send it in through quarterly estimated payments to avoid the IRS underpayment penalty.
General information for Illinois, not tax advice. Confirm your specifics with a CPA.
Frequently asked questions
How much self-employment tax do I pay in Illinois?
The federal self-employment tax is 15.3% everywhere, including Illinois — 12.4% Social Security (up to the wage base) plus 2.9% Medicare. That's on top of federal income tax and Illinois state income tax (flat 4.95%).
Does Illinois have a state income tax on freelance income?
Illinois charges a flat 4.95% state income tax on your net earnings.
How much should a freelancer in Illinois set aside for taxes?
A common rule of thumb is 25–30% of net profit, but Illinois's state income tax pushes the total higher. Use the Self-Employment Tax Calculator to get your exact set-aside from your profit and filing status.