Illinois sits in the middle of the road for freelancers. It has a state income tax, but it’s a flat rate rather than a progressive one, which makes it easier to estimate. It also has some specific rules for LLCs, local licensing, and a law that protects freelancers who need to get paid.
This guide covers the main points. It is educational, not tax or legal advice. Verify details with the Illinois Department of Revenue or a tax professional.
The Layers of Tax in Illinois
As a freelancer in Illinois, you generally pay:
- Federal income tax and self-employment tax. See Self-Employment Tax Explained.
- Illinois state income tax on your net profit.
Illinois doesn’t have city or county income taxes, so you don’t pay a separate local income tax, even in Chicago.
Illinois Income Tax Basics
- Illinois uses a flat income tax rate, currently 4.95%. Everyone pays the same rate on taxable income, no matter how much they earn. Confirm the current rate on the Illinois Department of Revenue website.
- You file Form IL-1040, which generally starts from your federal adjusted gross income. Your Schedule C profit flows through.
- Illinois has its own exemption allowance, and some federal items are treated differently, so your state taxable income may not match your federal figure exactly.
Because the rate is flat, a rough estimate is simple: multiply your expected Illinois taxable income by the state rate. Always confirm with current forms or software.
Illinois Estimated Tax Payments
Freelancers who expect to owe more than a minimum amount of Illinois tax for the year (check the current threshold) generally need to make estimated payments.
- Use Form IL-1040-ES or the state’s online payment system.
- Illinois generally follows the same four due dates as the IRS, with equal payments of 25%: April 15, June 15, September 15, and January 15. Confirm the dates each year.
- Federal and state payments are separate. Paying the IRS doesn’t satisfy Illinois.
- You can avoid underpayment penalties by meeting safe harbor rules, which are based on this year’s or last year’s tax.
For the federal side of the calendar, see our Freelance Tax Deadlines: 2026–2027 Calendar.
Forming an LLC in Illinois
If you form an LLC, expect these steps and costs:
- File articles of organization with the Illinois Secretary of State, which includes a filing fee.
- Name a registered agent with an Illinois address.
- File an annual report with a fee, due each year around your LLC’s anniversary month. Missing it can lead to penalties and possible administrative dissolution.
Illinois doesn’t require a newspaper publication for LLCs, unlike some other states.
Fees change, so verify them on the Illinois Secretary of State website. To weigh whether an LLC fits you, read Sole Proprietor vs. LLC. For the general steps, see How to Register a Freelance Business in Your State.
The Personal Property Replacement Tax
Illinois has a Personal Property Replacement Tax (PPRT) that applies to certain business entities such as partnerships, S-corporations, and trusts. A single-member LLC taxed as a sole proprietor is generally not subject to it, but if you elect S-corp status, it can apply. See When Does an S-Corp Make Sense for Freelancers? and talk to a professional before electing.
Illinois also has an elective pass-through entity tax for some entities. It’s a complex area, so ask a tax professional whether it applies to you.
Sole Proprietors and Business Names
Sole proprietors using their own legal name generally don’t need a state registration to begin. If you operate under a business name other than your own, you must typically register an assumed name with your county clerk. Check your county’s requirements and fees.
Sales Tax
- The Illinois state sales tax rate is 6.25%, and local governments add their own, so combined rates vary by location and can be higher in places like Chicago.
- If you sell physical products, you generally need to register with the Department of Revenue, collect tax, and file returns.
- Illinois doesn’t tax most professional services, but a few exceptions exist. Check with the Department of Revenue if you’re unsure.
Local Licenses and Permits
Many Illinois cities and counties require business licenses, and Chicago has its own licensing system that applies to many types of businesses. Home-based freelancers may also face zoning or home occupation rules. Many professions require state licenses as well.
See Do Freelancers Need a Business License? for how to find out what applies to you.
The Illinois Freelance Worker Protection Act
Illinois has a law designed to protect freelancers, which went into effect in 2024. In general, it provides that:
- Contracts for freelance work above a certain amount should be in writing and include key terms such as the scope of work, payment amount, and payment date.
- Freelancers should be paid on time, generally by the date in the contract or within 30 days after completing the work if none is stated.
- Hiring parties can’t retaliate against freelancers who assert their rights.
- Freelancers may have a way to file complaints with the Illinois Department of Labor or pursue legal remedies if they’re not paid.
The exact thresholds and requirements matter, so read official summaries before relying on the law. Written contracts help protect you under this law and in any state.
Hiring Help
If you hire employees, you generally need to register for Illinois unemployment insurance and withholding. Classifying workers correctly matters, because misclassifying an employee as a contractor can lead to penalties.
Working With Clients in Other States
- If you physically perform work in another state, that state may require you to file and pay tax on income earned there.
- Illinois has agreements with some nearby states that can affect how income is taxed for people who live in one and work in another. Check the Illinois Department of Revenue if this applies to you.
- Keep records of where you work.
Deductions Still Matter
Most business expenses that are deductible federally are also deductible for Illinois purposes, since the state starts from federal income. Common ones include:
- Software, equipment, and supplies
- Home office expenses (if you qualify)
- Business mileage. See tracking mileage for freelance deductions.
- Professional fees and licenses
- Retirement contributions. See SEP IRA vs. Solo 401(k).
Use our Year-End Tax Planning Checklist and Last-Minute Tax Deductions guide to review your options each year, and keep records with a simple bookkeeping system.
Illinois Freelancer Checklist
- ☐ Estimate your federal and Illinois tax each year
- ☐ Make federal and Illinois estimated payments
- ☐ Decide between sole proprietor and LLC
- ☐ Register an assumed name with your county clerk, if needed
- ☐ File your LLC annual report on time, if you have an LLC
- ☐ Check whether you need a sales tax registration
- ☐ Check local and professional license requirements
- ☐ Use written contracts that meet the Freelance Worker Protection Act
- ☐ Track any work done in other states
Common Mistakes
- Skipping Illinois estimated payments. Federal payments don’t cover them.
- Forgetting the LLC annual report.
- Not registering an assumed name when using a business name.
- Ignoring Chicago or other local licensing.
- Working without a written contract. It weakens your position if a client doesn’t pay.
Frequently Asked Questions
Do freelancers in Illinois pay state income tax?
Yes. Illinois taxes net self-employment income at a flat rate.
Is there a city income tax in Chicago?
No. Illinois doesn’t have local income taxes, but local licenses and sales taxes apply.
When are Illinois estimated taxes due?
Generally on the same four dates as federal estimated taxes. Confirm each year.
Do I need an LLC in Illinois?
Not required. An LLC can add liability protection but comes with fees and an annual report.
Do I need a written contract in Illinois?
For work above a certain value, the Freelance Worker Protection Act generally requires one. It’s a good practice regardless.
Final Thoughts
Illinois is easier than some states because of its flat income tax and no local income taxes. Keep up with estimated payments, file LLC annual reports on time, check local licensing, and use written contracts to protect your income.
Disclaimer: This article is for informational and educational purposes only and does not constitute tax, legal, or financial advice. Tax rates, fees, and rules change and depend on your situation. Verify current information with the Illinois Department of Revenue, the Illinois Secretary of State, or a licensed tax professional.
Last Update: October 12, 2026