How to Form an LLC in Illinois

Forming an LLC in Illinois means filing formation documents with the Illinois Secretary of State and paying a $150 filing fee. The steps below follow the order most founders work in, from checking the name to setting up ongoing compliance. Illinois charges $75 for the report, filed every year, so plan for that from the start.

Step 1: Choose and check your LLC name

Your Illinois LLC name must be distinguishable from other registered entities and include a designator such as "Limited Liability Company," "LLC," or "L.L.C." Search the state's business database through the Illinois filing office before you commit to a name, and check that a matching domain and trademark are free. Many states let you reserve a name for a short period for a small fee if you need time before filing.

Step 2: Appoint a registered agent

Every Illinois LLC needs a registered agent with a physical street address in the state who can accept legal papers during business hours. You can serve as your own agent if you live in Illinois, appoint a co-owner who does, or hire a commercial service. Our registered agent guide covers the trade-offs.

Step 3: File the formation document

File the Articles of Organization (some states call it a Certificate of Formation) with the Illinois Secretary of State. The filing fee is $150. Online filing is available in most states and is usually faster than mail. Processing times and expedite options vary, so check the current schedule before you file.

Step 4: Write an operating agreement

An operating agreement sets out ownership, management, voting, profit splits, and what happens if a member leaves. Illinois may not require you to file it, but having one supports your liability protection and settles disputes before they start. Single-member LLCs benefit too, because it documents that the business is separate from you. See the operating agreement guide for a clause outline.

Step 5: Get an EIN and open a business bank account

Apply for a free Employer Identification Number on IRS.gov. Never pay a third party for this. With the formation document and EIN you can open a business bank account, which keeps personal and business money apart.

Step 6: Handle ongoing filings and taxes

Illinois charges $75 for the report, filed every year. Illinois also has an entity-level tax to plan for: Personal Property Replacement Tax 1.5%. Illinois taxes personal income, so LLC owners report their share of profit on a Illinois return in addition to the federal one. Put every deadline on a calendar the day you form, because missed reports can lead to penalties and administrative dissolution.

Step 7: Register for local licenses and state taxes

Check city and county requirements wherever you operate in Illinois. Many municipalities require a business license even for home-based or online businesses. If you sell taxable goods or services, register with the Illinois tax agency for a sales tax permit, and register as an employer before you hire.

Illinois LLC at a glance

How Illinois compares

Illinois's LLC filing fee is $150, $50 above the national median of $100. 37 of the 51 jurisdictions (50 states and DC) charge less to file. Filing fees are only part of the picture, so the table below sets Illinois beside five states founders often consider.

Forming outside the state where you live and work rarely saves money. A business operating in Illinois that forms elsewhere generally still has to register as a foreign LLC in Illinois and pay both states' fees. Our best states for an LLC guide explains when an out-of-state filing makes sense.

Illinois specific notes

Illinois LLCs are subject to the Personal Property Replacement Tax of 1.5% on net income, in addition to flow-through state income tax on members.

What it costs to get started

State fees for the first year come to $225 for the filing and the first annual report, before optional extras such as a commercial registered agent, expedited processing, or a certified copy of your formation document. The Illinois LLC cost breakdown shows the full picture.