How to Form an LLC in Illinois: Steps & Cost (2026)
You form an Illinois LLC by filing Articles of Organization (Form LLC-5.5) with the Illinois Secretary of State and paying the $150 filing fee. File it online through the Department of Business Services, or by mail. You must appoint an Illinois registered agent, and every Illinois LLC must file a $75 annual report with the Secretary of State each year.
Quick Answer
- Form
- Form LLC-5.5, Articles of Organization
- Filing fee
- $150 (2026), to the Illinois Secretary of State
- Agency
- Illinois Secretary of State - Department of Business Services
- Registered agent
- Required - an Illinois resident or authorized entity with an Illinois office
- Annual report
- Form LLC-50.1, $75, due before the first day of the anniversary month
- State replacement tax
- 1.5% on Illinois net income for LLCs taxed as partnerships
Illinois Agency and Form: Secretary of State, Form LLC-5.5
An Illinois LLC is created by filing Articles of Organization with the Illinois Secretary of State, Department of Business Services. The correct document for a limited liability company is Form LLC-5.5. Filing this document - and the Secretary of State's acceptance of it - is the legal act that brings the LLC into existence under the Illinois Limited Liability Company Act, codified at 805 ILCS 180.
Form LLC-5.5 asks for the LLC's name, the address of its principal place of business, the name and address of its registered agent and registered office, the purpose, whether the LLC is member-managed or manager-managed, the names and addresses of the managers or managing members, and the organizer. The name must contain an LLC designator (such as "LLC," "L.L.C.," or "Limited Liability Company") and be distinguishable in the records of the Secretary of State from existing entity names. You can search existing names and file online through the Department of Business Services, which is the fastest route; mailed filings are also accepted. This guide covers the general Illinois process; for the national overview see how to form an LLC and the definition of what an LLC is.
How to Form an Illinois LLC, Step by Step
Forming an Illinois LLC is a five-step process centered on Form LLC-5.5. Each step below corresponds to a requirement of the Illinois Limited Liability Company Act or a federal tax rule.
- Choose and check your LLC name. Select a name that includes an LLC designator and is distinguishable from names already on file with the Secretary of State. Verify availability in the Department of Business Services entity database. If you are not ready to file, you may reserve the name by application for a $25 fee. Confirm the name also does not infringe a federal trademark.
- Appoint an Illinois registered agent. Every Illinois LLC must designate a registered agent with a physical Illinois street address (the registered office). The agent must be an individual Illinois resident or an entity authorized to transact business in Illinois. See the national registered agent overview for the general concept.
- File the Articles of Organization (Form LLC-5.5). Submit Form LLC-5.5 to the Illinois Secretary of State and pay the $150 filing fee. File online through the Department of Business Services for the quickest turnaround, or send the form by mail. Once the Secretary of State accepts it, your LLC legally exists.
- Adopt an operating agreement. Illinois does not require you to file an operating agreement, but one is strongly recommended to set ownership percentages, management structure, voting, and profit distribution. The Illinois LLC Act supplies default rules only where your agreement is silent.
- Get an EIN and register for Illinois taxes. Apply for a free federal EIN from the IRS, then register with the Illinois Department of Revenue using Form REG-1 for any tax accounts your business needs, such as sales tax or withholding.
After these steps, open a business bank account (banks generally ask for the stamped Articles of Organization and the EIN), and keep your registered agent and annual report current every year. Compare the full price of formation on our Illinois LLC cost page.
Two points trip up new filers. First, the LLC does not legally exist until the Secretary of State accepts the Articles of Organization - not when you submit them - so wait for confirmation before signing contracts in the LLC's name. Second, the operating agreement is internal and never filed with the state, yet banks and investors often ask to see it, so adopt one even though Illinois does not require it. Handling both correctly at the start prevents rework later.
Illinois LLC Filing Fees (2026)
The core cost of an Illinois LLC is the $150 Articles of Organization fee. The table below lists the state fees most new LLCs encounter, each verified against the fee schedule in the Illinois Limited Liability Company Act (805 ILCS 180/50-10). Amounts are effective for 2026 and are set by statute, not by any filing service.
| Item | Form | Fee (2026) | Agency |
|---|---|---|---|
| Articles of Organization (create the LLC) | Form LLC-5.5 | $150 | Secretary of State |
| Articles of Organization - series LLC | Form LLC-5.5(S) | $400 | Secretary of State |
| Annual report | Form LLC-50.1 | $75 | Secretary of State |
| Application to reserve a name | Form LLC-1.15 | $25 | Secretary of State |
| Change of registered agent / office | Form LLC-1.36/1.37 | $25 | Secretary of State |
| Federal EIN | IRS Form SS-4 | $0 (free) | IRS |
| Business tax registration | Form REG-1 | $0 (free) | Dept. of Revenue |
Expedited processing is available from the Secretary of State for an additional fee if you need faster handling. Because expedite fees and copy charges are not fixed in the LLC Act's fee schedule and can change, confirm the current amount with the Department of Business Services before you file.
Illinois Registered Agent Requirement
An Illinois registered agent is the person or entity your LLC designates to receive service of process and official state correspondence. Section 1-35 of the Illinois LLC Act requires every domestic and foreign LLC to continuously maintain a registered agent and a registered office in Illinois. You name the initial agent directly on Form LLC-5.5.
The agent must be either an individual who is a resident of Illinois, or a person authorized to transact business in Illinois, and must have a physical Illinois street address for the registered office. You may act as your own registered agent, name a manager, or hire a commercial registered agent service. To change agents later, file a statement of change with a $25 fee. If a registered agent resigns, they file written notice with the Secretary of State and mail a copy to the LLC at its principal office at least 10 days before filing. Failing to maintain a registered agent can lead to administrative dissolution of the LLC. See Illinois registered agent requirements for detail.
Illinois Annual Report
Every Illinois LLC must file an annual report (Form LLC-50.1) with the Secretary of State each year and pay a $75 fee. The report lists the LLC's name, its registered office and agent, its principal place of business, and the names and business addresses of its managers or managing members. Under Section 50-1 of the LLC Act, the report is due within the 60 days immediately preceding the first day of the LLC's anniversary month - the month in which the LLC was originally organized.
If the report and fee are not filed on time, Section 50-15 imposes a $100 penalty, and continued delinquency can lead to administrative dissolution of the LLC. There is no state income tax component to this filing; the annual report is purely a Secretary of State requirement. For the full schedule and how to file, see Illinois annual report and taxes.
EIN, Illinois Taxes, and the Replacement Tax
A federal Employer Identification Number (EIN) is issued free by the IRS and is used to open a bank account, hire employees, and file taxes. By default, the IRS treats a single-member LLC as a disregarded entity (taxed on the owner's return) and a multi-member LLC as a partnership; either can elect corporate or S-corporation treatment by filing the appropriate IRS form.
At the state level, Illinois imposes a personal property replacement tax. An LLC taxed as a partnership pays replacement tax at 1.5% of its Illinois net income and files Form IL-1065; an LLC taxed as a corporation pays 2.5% and files Form IL-1120. Individual members then pay Illinois individual income tax at 4.95% on their distributive shares. If your LLC sells taxable goods or services, register with the Illinois Department of Revenue using Form REG-1 and obtain a Certificate of Registration to collect the 6.25% state Retailers' Occupation (sales) Tax. See business licensing in Illinois for what registrations your activity requires.
Penalties for Missing Illinois Requirements
Missing Illinois requirements carries real consequences. If an LLC fails to file its annual report, the Secretary of State assesses a $100 penalty and can ultimately administratively dissolve the entity, which ends its authority to conduct business under its name. To restore a dissolved LLC, you must file an application for reinstatement and pay a $200 reinstatement fee plus all delinquent annual reports and penalties.
Separately, if an LLC does not maintain a registered agent and registered office, the Secretary of State may administratively dissolve the entity after notice. Keeping your registered agent current and filing the annual report on time each year is the simplest way to avoid these outcomes.
Closing an Illinois LLC
To close an Illinois LLC properly, you wind up the business, settle debts and taxes, and file a Statement of Termination (Form LLC-35.15) with the Secretary of State under Article 35 of the LLC Act. Simply abandoning the LLC leaves annual report obligations running and can trigger penalties. See how to dissolve an LLC in Illinois for the full wind-up and termination steps, and the national dissolution overview.
Frequently Asked Questions
How much does it cost to start an LLC in Illinois?
The state filing fee for Articles of Organization (Form LLC-5.5) is $150, paid to the Illinois Secretary of State. A series LLC costs $400. Each LLC then files a $75 annual report every year. See Illinois LLC cost.
What form do I file to create an Illinois LLC?
Form LLC-5.5, the Articles of Organization. File it online through the Department of Business Services, or by mail, with the $150 fee to the Illinois Secretary of State.
Does an Illinois LLC need a registered agent?
Yes. Every Illinois LLC must continuously maintain a registered agent and physical Illinois registered office. The agent must be an Illinois resident individual or an entity authorized to do business in Illinois.
How long does it take to form an Illinois LLC?
Online filings are generally processed fastest, often within a few business days, while mailed filings take longer. Expedited service is available for an additional fee; confirm the current amount and timeframe with the Secretary of State.
Does an Illinois LLC pay state income tax?
An LLC taxed as a partnership does not pay Illinois income tax itself but owes the 1.5% personal property replacement tax on Illinois net income and files Form IL-1065. Members pay Illinois individual income tax at 4.95% on their shares.
Related
- How to form an LLC (cluster hub)
- Illinois registered agent requirements
- Illinois LLC cost and filing fees
- Illinois LLC annual report and taxes
- How to get an EIN
- How to get a business license in Illinois
- How to dissolve an LLC in Illinois
- How much does an LLC cost?
More Illinois business guides
Business License In Dissolve An Llc In Annual Report Articles Of Organization Business Entity Search Certificate Of Formation Dba Filing Llc Cost Llc Tax Filing Operating Agreement Registered Agent
Sources
- Illinois LLC Act - 805 ILCS 180/50-10, Fees ($150 Articles of Organization; $400 series; $75 annual report; $25 name reservation; $25 change of agent; $200 reinstatement).
- Illinois LLC Act - 805 ILCS 180/1-35, Registered office and registered agent.
- Illinois LLC Act - 805 ILCS 180/50-1, Annual report (due within 60 days before the anniversary month).
- Illinois LLC Act - 805 ILCS 180/50-15, Penalties ($100 late penalty).
- Illinois LLC Act - 805 ILCS 180/5-5, Articles of organization.
- Illinois LLC Act - 805 ILCS 180/35-15, Statement of termination.
- Illinois Secretary of State - Limited Liability Companies (Department of Business Services).
- Illinois Department of Revenue - Business Registration (Form REG-1).
- Illinois Department of Revenue - Income Tax Rates (4.95% individual; 1.5% replacement tax for partnerships).
- Illinois Department of Revenue - Partnerships (Form IL-1065).
- IRS - Limited Liability Company (LLC) (federal default classification).
- IRS - Get an Employer Identification Number (free EIN).
- Legal Information Institute - 26 CFR § 301.7701-3, Classification of certain business entities.
LegalGlass provides general information for educational purposes and is not a law firm or a substitute for advice from a licensed attorney or tax professional. Laws, fees, and thresholds change; verify current requirements with the Illinois Secretary of State and Illinois Department of Revenue before acting.