StructureCost2026

What an LLC costs in Illinois (2026)

Forming an LLC in Illinois costs $150. After that the state charges Annual Report (Form LLC-50.1), $75 a year, and LLCs owe Illinois personal property replacement income tax (partnerships and S corps).

CostAmountWhen
Articles of Organization (Form LLC-5.5)$150Once, to formilsos.gov
Annual Report (Form LLC-50.1)Annual Report (Form LLC-50.1), $75 a yearBefore the first day of the anniversary month of organizationilsos.gov
Illinois personal property replacement income tax (partnerships and S corps)$1,500 at $150,000 revenueYearlytax.illinois.gov

LLC taxes in Illinois by revenue

RevenueIllinois personal property replacement income tax (partnerships and S corps)Total with report fee
$50,000$500$575
$150,000$1,500$1,575
$500,000$5,000$5,075
$1,000,000$10,000$10,075
$3,000,000$30,000$30,075

Profit taken as two thirds of revenue where a tax is on net income.

Illinois personal property replacement income tax (partnerships and S corps): Applies to LLCs taxed as partnerships. A single-member LLC disregarded for tax is not subject, since its owner files as an individual. C corps pay 2.5%, included in corporate_income_tax.

What else an LLC owner pays

The fees above are what the state charges the LLC. The bigger cost is tax on the profit: a single-member LLC pays the same income tax and self-employment tax as a sole proprietor. At $100,000 of profit that comes to $27,842 a year in Illinois, fees included. An S corp election can lower it: LLC vs S corp in Illinois.

Series LLCs pay $400 to form and $50 per series on the annual report. $100 penalty if the report is late.

Questions

How much does it cost to start an LLC in Illinois?

$150 to file the Articles of Organization (Form LLC-5.5).

How much does an LLC cost per year in Illinois?

Annual Report (Form LLC-50.1), $75 a year, plus Illinois personal property replacement income tax (partnerships and S corps): $1,500 for a business with $150,000 of revenue and $100,000 of profit.

When is the Illinois LLC report due?

Before the first day of the anniversary month of organization.

Does an LLC pay Illinois income tax?

Not by itself, in most cases: a single-member LLC's profit is taxed on the owner's return. Illinois taxes personal income at a flat 4.95% (2026).

Other states