How to Start a Business in Illinois
Illinois is home to more than 1.2 million small businesses that employ nearly 2.5 million workers across the state.
In This Article
The Complete Guide
How to Start a Business in Illinois — 12 Steps
This is a full walkthrough: entity selection, state registration, federal tax IDs, licenses, banking, insurance, and ongoing compliance. Every step includes the official Illinois links, fees, and timelines.
Cost depends on your structure. A sole proprietorship may cost nothing to start. An LLC costs $150 to file online. A corporation costs $175. Step 3 walks through every option.
Illinois: Key Business Facts
Updated: Feb 2026- LLC Filing Fee (Online)
- $150
- Sole Proprietorship / DBA
- $30
- Corporation Filing
- $175
- Processing Time
- 5-10 business days
- Expedited Option
- $100 / 24 hours
- State Income Tax
- 4.95% flat rate
- Sales Tax Rate
- 6.25%
- Gross Receipts Tax
- No
- Franchise / Annual Tax
- None
- Filed With
- Illinois Secretary of State
- State Business License
- Not required (check local)
- Last Verified
- February 24, 2026
Local licenses: Illinois does not require a general state business license. Most cities and counties require their own business licenses, with fees ranging from $40 in suburban areas to over $1,000 in Chicago.
What It Takes to Start a Business in Illinois
Forming an LLC in Illinois costs $150 through the Illinois Secretary of State, with standard processing taking 5 to 10 business days. The state charges a flat 4.95% income tax rate and a 6.25% base sales tax, both of which affect how you plan your finances from day one.
You will also need an EIN from the IRS, a business bank account, and any local licenses required by your city or county. The Illinois Small Business Development Center network offers free consulting to help you build a plan and access funding.
Validate Your Business Idea in Illinois
Test your business concept against Illinois market demand before investing time or money. The state's economy supports diverse sectors, and your idea should align with where real spending is happening.
- Finance and insurance (Chicago is a global financial hub)
- Manufacturing (food processing, machinery, chemicals)
- Healthcare and social assistance (one of the state's largest employers)
Contact the Illinois Small Business Development Center (SBDC) for free one-on-one market research consultations and feasibility analysis.
Pro Tip
Write a Business Plan
Draft a business plan that covers your revenue model, target customers, startup costs, and 12-month financial projections. Banks and SBA lenders require a formal plan before approving any financing.
Use our business plan guide to structure each section correctly. The Illinois SBDC also offers free plan-review workshops across the state.
Pro Tip
Choose Your Business Structure in Illinois
Most founders in Illinois choose an LLC because it combines personal liability protection with pass-through taxation and minimal paperwork. Filing an LLC costs $150 at the Illinois Secretary of State.
The four main structures are sole proprietorship, LLC, S-Corp, and C-Corp. Each has different tax treatment, liability exposure, and formation requirements. See the full comparison below before deciding, and read our Illinois LLC formation guide for detailed instructions.
Pro Tip
Important
Business Structure Comparison — Illinois
Full comparison guide| Structure | Illinois Filing Cost | Personal Liability | How You're Taxed | Best For |
|---|---|---|---|---|
| Sole Proprietorship | $30 (DBA) | ❌ None | Personal income tax. No separate return. | Freelancers, consultants, side hustles testing an idea with no employees. |
| LLC Most Common | $150 online | ✅ Personal assets protected | Pass-through by default. Elect S-Corp when profitable. | Most small businesses. Best balance of liability protection, flexibility, and tax options. |
| S-Corporation | ~$150 + IRS election | ✅ Personal assets protected | Pass-through. Owners pay themselves a salary — can reduce self-employment tax. | Profitable businesses (typically $50K+ net) where payroll tax savings justify the complexity. |
| C-Corporation | $175 | ✅ Personal assets protected | Corporate tax rate (21% federal). Double taxation on dividends. | Startups planning to raise VC funding, issue stock options, or eventually go public. |
| General Partnership | Free / No State Filing | ❌ None — all partners personally liable | Pass-through. Each partner reports share on personal return. | Two or more owners who trust each other and don't need liability protection. |
Which should you choose? Most first-time founders in Illinois pick an LLC — it protects your personal assets without the complexity of a corporation. If you're not sure, consult a CPA or business attorney before filing. Read the full Illinois LLC guide →
Choose and Register Your Business Name
Search the Illinois Secretary of State business database to confirm your desired name is available. Your LLC name must include "LLC" or "Limited Liability Company" as a designator.
You can reserve a name for 90 days by filing a Name Reservation with the Secretary of State for $25. If you operate under a different name than your legal entity name, file an Assumed Business Name (DBA) for $30 per year.
Pro Tip
Check Illinois Business Name Availability
Search the official Illinois Secretary of State database before you file.
Register Your Business with the State
File your Articles of Organization with the Illinois Secretary of State online for $150. Standard processing takes 5 to 10 business days, or pay an additional $100 for 24-hour expedited processing.
You will receive a Certificate of Organization once approved. Every Illinois LLC must designate a registered agent with a physical Illinois address. See our Illinois registered agent guide for affordable options.
Pro Tip
Important
File Online with Illinois Secretary of State
Official Illinois business registration portal. Standard processing: 5-10 business days.
Get Your Federal EIN from the IRS
Apply for a free Employer Identification Number (EIN) at the IRS website. The online application takes about 10 minutes and you receive your EIN immediately.
You need an EIN to open a business bank account, hire employees, and file federal taxes. Even single-member LLCs should get one to keep personal and business tax filings separate.
Pro Tip
Get Your Illinois Licenses and Permits
Requirements vary by industry and location, but most Illinois businesses need some combination of the following:
- Sales Tax Permit - required if selling taxable goods or services; register free at the Illinois Department of Revenue MyTax portal
- Local Business License - Illinois has no general state business license, but most cities and counties require one (Chicago licenses start at $250+, suburban areas typically $40 to $100)
- Professional License - required for contractors, healthcare providers, real estate agents, accountants, and other regulated fields through the Illinois Department of Financial and Professional Regulation (IDFPR)
- Employer Registration - required before hiring; register with the Illinois Department of Employment Security (IDES) for unemployment insurance
Pro Tip
Important
Open a Business Bank Account
Bring your EIN confirmation, Articles of Organization, government-issued ID, and your LLC operating agreement to open a dedicated business checking account. Separating personal and business finances is essential for maintaining your LLC's liability protection.
Compare fee structures and features using our best business bank accounts guide. Many Illinois banks and credit unions offer free business checking for the first year.
Pro Tip
Set Up Accounting and Understand Illinois Taxes
Illinois charges a flat 4.95% personal income tax rate on pass-through business income and a 7% corporate income tax rate for C-Corps. The state sales tax is 6.25% at the base level, with local additions pushing combined rates to 10%+ in some areas like Chicago.
Register with the Illinois Department of Revenue to file and pay state taxes online. Set up quarterly estimated tax payments to avoid underpayment penalties from both the IRS and the state.
Choose accounting software that tracks Illinois-specific sales tax rates automatically. Our accounting software comparison covers the best options for small businesses.
Pro Tip
Get Business Insurance in Illinois
Illinois requires workers' compensation insurance for all businesses with employees, with no exceptions for small employers. Even if you have just one part-time employee, you must carry a policy or face penalties.
General liability insurance is the baseline policy for every business, typically costing $400 to $1,500 per year depending on your industry. Compare quotes using our business insurance guide to find the right coverage at the best price.
Important
Build Your Online Presence
Claim your free Google Business Profile to appear in local search results across Illinois. This is the single highest-impact marketing step for local businesses, especially if you serve customers in a specific metro area.
Build a simple website with your services, contact info, and customer reviews. Our website builder comparison covers platforms that get you live in under a day.
Pro Tip
Stay Compliant After Forming Your Illinois Business
After forming, keep your Illinois business in good standing by meeting these ongoing requirements:
- Annual Report - due before the first day of your LLC's anniversary month each year, fee: $75 (file at ilsos.gov)
- State Tax Filings - file annual Illinois income tax returns and quarterly estimated payments through the Illinois Department of Revenue
- Registered Agent - maintain a registered agent with a physical Illinois address at all times
- Business Licenses - renew any city or county licenses annually (check your municipality's renewal schedule)
Missing the annual report deadline triggers a $100 late fee if filed more than 60 days past due, and continued noncompliance leads to administrative dissolution. Track all deadlines with StartupOwl's compliance calendar.
Pro Tip
Important
Illinois Business Background & Context
State-specific data to help you plan — taxes, economy, funding, and what to expect after you form.
Frequently Asked Questions
What to Do Next
Once you've registered your Illinois business, take these steps to set up for success.
Form Your Illinois LLC
Follow our step-by-step guide to file your Articles of Organization with the Illinois Secretary of State for $150.
Start Your LLC →
Get a Registered Agent in Illinois
Compare top registered agent services that provide a compliant Illinois address and handle your legal documents.
Compare Agents →
Open a Business Bank Account
Find the best business checking account with low fees and features designed for small business owners.
Compare Accounts →
Register with the Illinois Department of Revenue
Set up your sales tax permit and income tax accounts through MyTax Illinois to stay compliant from day one.
Register for Taxes →
Get Business Insurance
Compare general liability and workers' comp quotes to protect your Illinois business and meet state requirements.
Get Covered →
Disclaimer: This guide is for informational purposes only and does not constitute legal or tax advice. Requirements change — always verify current fees and requirements directly with Illinois Secretary of State and the IRS before filing.
Ready to Form?
Get your Illinois business registered with ZenBusiness — choose your structure, file the paperwork, and stay compliant from day one.
About the Author
Director of Entrepreneurial Strategy
Jennifer is a former founder who built and sold a boutique B2B logistics company in her thirties. She understands the emotional and strategic toll of building a business from the ground up without a massive safety net. She is deeply connected to the Atlanta startup ecosystem and is passionate about equitable funding.
Was this article helpful?