Form a Business in Illinois

What makes Illinois different

• Annual Report due BEFORE the FIRST day of anniversary month (not last day). This is unique. LLC formed Jan 15 → AR due by Dec 31 of every year (the month BEFORE Jan). Most other states use last-day-of-anniversary-month. Wizard math must shift back one month.
• Illinois has TWO franchise tax events for Corps. (a) Initial Franchise Tax at formation: $1.50 per $1,000 of paid-in capital, $25 minimum. (b) Annual Franchise Tax at AR time: 0.1% on Illinois portion of paid-in capital, $25 minimum prior to 2025 changes.…
• Franchise Tax phase-out was REVERSED in 2021 (P.A. 102-16). A 2019 law had planned full repeal by 2024; that was undone. HB 5526 (introduced Feb 2026) proposes full repeal effective Jan 1, 2028: track this bill, it would simplify IL Corp filings…
• Illinois LLC and Corp formation fees are identical at $150. Atypical. Most states have a notable LLC/Corp formation fee gap. Annual Report is identical at $75 too. So at the SOS level, IL doesn't push customers toward one entity vs the other.
• IL Replacement Tax (PPRT, "Personal Property Tax Replacement Income Tax") is the entity-level income tax filed at the DOR (NOT SOS). Replaces the IL personal property tax abolished in 1979. Corp pays 2.5%, LLC/Partnership/Trust pays 1.5% of net…
• Total IL tax stack for a profitable C-Corp: 9.5% (7% CIT + 2.5% PPRT). Among the highest combined state rates in the US.
• Total IL tax stack for an LLC member: 1.5% PPRT at entity + 4.95% personal income tax on K-1 income = ~6.45% combined.
• Series LLC permitted. Illinois was an early Series LLC adopter (805 ILCS 180/37-40). $50 per series. Useful for real estate holding structures.

Ready to file in Illinois?

We handle Articles of Organization, registered agent service, annual report monitoring, and ongoing compliance, backed by our canonical Illinois ruleset (re-verified quarterly against Illinois Secretary of State, Department of Business Services).

Filing portal: https://apps.ilsos.gov/