Complete Guide to Forming an LLC in Illinois
Based on official requirements from the Illinois Secretary of State, Internal Revenue Service, and Illinois Department of Revenue
Bottom Line Up Front
Illinois LLC Formation requires four core steps: File Articles of Organization with the Illinois Secretary of State ($150 fee), obtain an Employer Identification Number (EIN) from the Internal Revenue Service (free), register with the Illinois Department of Revenue (free), and file annual reports ($75/year). Processing time: 5-10 business days for online filing.
1 Choose and Verify Your LLC Name
Illinois LLC Name Requirements
The Illinois Secretary of State requires LLC names to:
- • Include "Limited Liability Company," "LLC," or "L.L.C." in the business name
- • Be distinguishable from existing Illinois entities in the state database
- • Avoid prohibited words like "bank," "insurance," or government terms without authorization
Name Verification Process
Search the Illinois Secretary of State database → Confirm name availability → Reserve name (optional)
Name Reservation Details:
- Cost: $25 reservation fee
- Duration: 90 days from approval
- Method: Online through Illinois Secretary of State website or by mail
- Authority: Illinois Secretary of State
2 Appoint an Illinois Registered Agent
Registered Agent Requirements
Illinois law under 805 ILCS 180/1-35 requires every LLC to maintain a registered agent who:
- • Must have a physical Illinois street address (P.O. boxes not accepted)
- • Must be available during normal business hours to receive legal documents
- • Acts as official point of contact for service of process and state correspondence
Registered Agent Options
1. Yourself
If you have an Illinois address and are 18+ years old
2. Another Individual
Illinois resident, 18+ years old
3. Professional Service
Recommended for privacy and reliability
3 File Articles of Organization
Required Information for Articles of Organization
The Illinois Secretary of State requires these details in Form LLC-5.5:
- • LLC name (as verified in Step 1)
- • Registered agent name and Illinois street address
- • Organizer information (person filing the Articles)
- • Management structure (member-managed or manager-managed)
Filing Methods and Fees
✓ Online Filing (Recommended)
- Process: Illinois Secretary of State online portal
- Fee: $150
- Processing Time: 5-10 business days
- Payment: Credit card (Visa, MasterCard, Discover, or American Express)
- Expedited: $100 additional for 1-2 business days
Mail Filing
- Fee: $150
- Processing Time: 7-14 business days plus mail time
- Required Forms: Articles of Organization (Form LLC-5.5)
- Payment: Certified check or money order payable to "Illinois Secretary of State"
Secretary of State
Department of Business Services
Limited Liability Division
501 S 2nd Street, Room 351
Springfield, IL 62756
4 Obtain Federal Employer Identification Number (EIN)
⚠ Important: Apply Direct with IRS
The IRS EIN application is FREE. Beware of fee-charging websites that claim to expedite the process. Apply directly at IRS.gov.
EIN Application Process
Required for:
- • Federal tax filing
- • Opening business bank accounts
- • Hiring employees
- • Business credit applications
Application Process:
- Authority: Internal Revenue Service (IRS)
- Cost: Free (beware of fee-charging websites)
- Method: Online at IRS.gov
- Processing: Immediate approval
• LLC name (exactly as filed with Illinois Secretary of State)
• Illinois business address
• Responsible party information (SSN or ITIN required)
• Business start date
• Reason for applying (starting new business)
5 Register with Illinois Department of Revenue
Business Registration Requirement
Illinois Department of Revenue requires LLCs to register if conducting business in Illinois or with Illinois customers. Registration is free and provides:
- • Certificate of Registration (acts as general business license)
- • Illinois taxpayer identification number
- • Authorization to conduct business in Illinois
Registration Process
Registration Details:
- Method: MyTax Illinois
- Processing Time: 1-2 business days
- Cost: Free
Common Tax Registrations:
- • Income Tax (automatic for LLCs)
- • Sales and Use Tax (if selling goods)
- • Withholding Tax (if hiring employees)
- • Personal Property Replacement Tax (1.5%)
Ongoing Compliance Requirements
Illinois LLC Annual Report
Annual Report Details:
- Requirement: All Illinois LLCs must file annual report
- Due Date: Before LLC anniversary month
- Fee: $75
- Late Penalty: $100 additional
- Authority: Illinois Secretary of State
Consequences of Non-Compliance:
- • $100 late penalty after 60 days
- • Administrative dissolution after 6 months
- • $200 reinstatement fee plus penalties
- • Loss of good standing with state
Tax Obligations
Illinois State Taxes:
- • Illinois Income Tax: 4.95% flat rate
- • Personal Property Replacement Tax: 1.5%
- • Sales Tax: 6.25% + local (if applicable)
For detailed tax information, visit the Illinois Department of Revenue.
Federal Taxes:
- • Self-Employment Tax on business income
- • Single-member: Schedule C
- • Multi-member: Form 1065
LLCs can elect S-Corp or C-Corp status by filing forms with IRS.
Timeline and Cost Summary
Formation Costs
Timeline
- • Online filing: 5-10 business days
- • Mail filing: 7-14 business days
- • Expedited processing: 1-2 business days (+$100)
- • EIN receipt: Immediate online
Ongoing Compliance Requirements
Illinois LLC Annual Report
Annual Report Details:
- Due Date: Before LLC anniversary month
- Fee: $75
- Late Penalty: $100 additional
- Authority: Illinois Secretary of State
Consequences of Non-Compliance:
- • $100 late penalty after 60 days
- • Administrative dissolution after 6 months
- • $200 reinstatement fee plus penalties
- • Loss of good standing with state
Tax Obligations
Illinois State Taxes:
- • Illinois Income Tax: 4.95% flat rate
- • Personal Property Replacement Tax: 1.5%
- • Sales Tax: 6.25% + local (if applicable)
Federal Taxes:
- • Self-Employment Tax on business income
- • Single-member: Schedule C
- • Multi-member: Form 1065
Need Professional Help?
While forming an LLC yourself is possible, professional formation services can ensure accuracy, provide ongoing support, and help you avoid costly mistakes. Many services offer comprehensive packages starting at $0 plus state fees.
Frequently Asked Questions
Do I need to live in Illinois to form an Illinois LLC?
No. Illinois allows non-residents to form and own LLCs, but you must maintain an Illinois registered agent with a physical Illinois address.
How long does the formation process take?
Standard online filing: 5-10 business days. Mail filing: 7-14 business days plus mail time. Expedited options available for $100 additional fee.
What happens if I don't file the annual report?
The Illinois Secretary of State will charge a $100 late penalty and may administratively dissolve your LLC if not filed within 6 months of the due date.
Can I change my LLC name after formation?
Yes, but it requires filing an Amendment to Articles of Organization with the Illinois Secretary of State and paying applicable fees.
Official Resources and Contact Information
Primary Authorities
| Agency | Function | Contact |
|---|---|---|
| Illinois Secretary of State | LLC formation, annual reports | ilsos.gov |
| Business Services Department | Articles of Organization filing | (217) 524-8008 |
| Internal Revenue Service | Federal EIN application | IRS.gov, (800) 829-4933 |
| Illinois Department of Revenue | State tax registration | tax.illinois.gov, (217) 785-3707 |
Online Resources
Formation and Filing
Tax and EIN Registration
Disclaimer: This guide is based on official requirements from the Illinois Secretary of State, Internal Revenue Service, and Illinois Department of Revenue as of 2025. Laws and procedures may change. Consult with legal and tax professionals for advice specific to your situation.