How To Start An LLC In Illinois (Mar. 2026) – Filing Guide

To officially start your Limited Liability Company (LLC) in Illinois, you must file your Articles of Organization with the Illinois Secretary of State and pay the $150 filing fee. This can be done using the online portal or by completing Form LLC-5.5 and submitting it by mail.

However, you’re not yet permitted to perform full business operations immediately after your formation documents are approved by the state. You must complete several important steps before and after submitting your Articles of Organization to ensure your LLC is properly set up and compliant with state law.

In this guide, you’ll learn how to start an LLC in Illinois yourself with my useful information.

How To Start An LLC In Illinois Online: A Step-By-Step Breakdown

Your Illinois LLC formation process is fairly straightforward if you can follow the state’s legal filing rules and requirements. I will list your main requirements and how to complete them below so you can get off to the best possible start.

1. Search And Choose Your Legal LLC Name

Your first step is to choose your legal LLC name. It must be unique and distinguishable compared to existing businesses registered in the state. Use the Illinois Department of Business Services Business Entity Search tool to check if your desired LLC name is available to use.

Furthermore, your proposed LLC name must follow the state’s naming rules and regulations. Otherwise, your formation documents will be rejected.

Learn how to use the search tool and the state rules that you must follow in my article: Illinois LLC Business Name Search.

2. Appoint A Registered Agent

Every Illinois LLC must appoint and maintain an official Registered Agent when operating in the state under the 805 Illinois Compiled Statutes (ILCS) 180/1-35.

Your Illinois Registered Agent serves as your official contact for receiving and processing legal documents, tax notices, and official state correspondence. They must:

• Have a physical street address in the state. This can NOT be a P.O. box.
• Be available during normal operating hours.

You have four main options when choosing who you want to be your Registered Agent in Illinois:

1. Yourself.
2. A family member.
3. A trusted friend.
4. A professional third-party Registered Agent service.

While you can appoint yourself or another individual as your Registered Agent, you create several compliance and privacy risks. This is because your Registered Agent’s name and address will be listed on the public records.

Therefore, I highly recommend using a professional third-party Registered Agent service. This protects your personal details and ensures that your compliance obligations are met.

If you need further guidance and comprehensive comparisons of the top providers, read my guide on the Best Illinois Registered Agent Services.

3. File Your Illinois Articles Of Organization

Under 805 ILCS 180/5-5(b), your LLC does NOT legally exist as a separate business entity until your Articles of Organization have been filed with and approved by the Illinois Secretary of State.

You can file using these two main methods. Each one has an associated $150 state filing fee:

• Online: Use the Illinois Secretary of State’s online portal. Your filing should be processed in 5-10 business days.
• By mail: Complete Form LLC-5.5 and mail it to the Secretary of State. This usually takes around 10–15 business days, plus mailing time to process.

I’ve provided a step-by-step guide for each filing method here: How To File Your Illinois Articles Of Organization.

4. Complete Your Operating Agreement

An Operating Agreement is a fundamental internal business document setting out how your LLC should be managed, owned, and operated. Under 805 ILCS 180/1-5, it can be oral, written, implied, or a combination of each. As an internal business document, it does NOT need to be filed with the Illinois Secretary of State or any other official state agency.

Completing a legally-binding Operating Agreement can override the default state rules, as long as it doesn’t conflict with state law. As indicated in 805 ILCS 180/15-1, an Illinois LLC is member-managed by default, unless stated otherwise in an Operating Agreement.

Therefore, I suggest that every Illinois LLC completes and maintains an Operating Agreement (Even single-member LLCs).

If you need help, you can download my Operating Agreement templates and start customizing them. I’ve made one for each LLC management structure.

5. Get Your LLC’s Employer Identification Number (EIN)

An EIN, also known as a federal tax ID, is a nine-digit federal identification number issued by the Internal Revenue Service (IRS). You need it to hire employees, open a dedicated business bank account, and file your federal taxes.

It’s completely free to obtain your EIN when applying online using the official IRS website.

Your filing method depends on your U.S. residency status:

• U.S. residents: Apply online using the official IRS website if you have a Social Security Number (SSN) or an Individual Taxpayer Identification Number (ITIN). You can read my guide on how to Obtain Your EIN By Online Submission for a full walkthrough.
• Non-U.S. residents: You must complete Form SS-4 and file it by mail or fax if you don’t have an SSN or an ITIN. Read my article for detailed instructions: Using Form SS-4 For Mail-In EIN Submission.

Online applications take approximately 15 minutes to complete, with your EIN immediately issued when finished. Filing your application by fax takes around 4 days, while mail filings take significantly longer (Up to 4 weeks).

You can read my article on How To Get An EIN For An Illinois LLC for more information.

6. Obtain Your Required Business Licenses

Your Illinois LLC licensing requirements are primarily determined by your operating location and business industry.

Example: A highly-regulated industry like contracting may require several state and local industry-specific business licenses alongside zoning permits.

I advise contacting the relevant authority to confirm your licensing needs before beginning business operations. This is because your licensing needs depend on your applicable agency.

See my guide on the Illinois LLC Business Licenses to find several useful resources.

7. Register With The Illinois Department Of Revenue

All Illinois LLCs need to register with the Illinois Department of Revenue for:

• A Certificate of Registration or License: This depends on your registered tax type.
• An Illinois Taxpayer ID Number: This is used for state tax reporting and compliance.

You can use three main methods to register with the Illinois Department of Revenue (all with no charge):

• Online: Use the MyTax Illinois portal to file Form REG-1. It should be processed in around 1-2 business days.
• By mail: Submit Form REG-1 by mail. Processing generally takes 4-6 weeks.
• In person: Visit an IDOR office, then complete and submit Form REG-1. Your application should be processed immediately.

For a step-by-step guide, you can read this article: Illinois Business Tax Registration.

What To Do Once Your Illinois LLC Is Approved

Once you’ve finished the main steps above, you must complete several important post-formation steps. This allows you to operate legally and maintain your good standing in the state.

1. Open A Dedicated Business Bank Account

Your first step should be to open a dedicated LLC business bank account. This protects your limited liability status and keeps your personal and business finances separate.

Furthermore, it enhances your financial transparency and simplifies your accounting processes.

2. File Your Annual Report

Under 805 ILCS 180/50-1, all Illinois LLCs and Corporations must file an Annual Report with the Illinois Secretary of State to stay active and maintain their good standing.

Your Illinois Annual Report is due before the first day of your anniversary month. This is the month that your LLC was initially approved in the state.

Your first Annual Report is due the year after your LLC formation year.

For example, if your LLC was formed on June 15, 2026, your report is due before June 1, 2027 and every year thereafter.

You can file your report up to 60 days before your due date, as long as you pay the $75 filing fee. This applies regardless of your filing method.

You have two main filing options to choose from:

• Online: Use the LLC Annual Report Filings portal on the Secretary of State’s website. Your filing will be processed immediately once submitted.
• By mail: Complete Form LLC-50.1 and send it to the Secretary of State Department of Business Services along with your payment voucher. It takes around 10-15 days to be processed.

Read my guide on How To File Your Illinois LLC’s Annual Report for a detailed breakdown.

3.  Renew Your Applicable Licenses & Permits

You need to acquire and renew your applicable licenses and permits to keep your LLC active and legally allowed to operate in the state. Without them, you face fines, penalties, and potential administrative dissolution.

a. Business Licenses

Illinois does NOT have a general business license requirement. Therefore, you do NOT have a general renewal schedule that you must follow.

However, most regulated professions require specific licenses that need to be renewed according to the Illinois Department of Financial & Professional Regulation. This is generally done using a three-year cycle for most LLCs. Alongside this, local business licenses are renewed annually (once a year), with different cities and counties setting their own renewal schedules.

b. Certificate Of Registration

Your registered LLC tax type determines when your Certificate of Registration or License expires.

You have three potential schedules:

• Annual expiration (automatic renewal).
• Manual expiration (manual renewal every two to three years).
• No expiration.

I recommend carefully researching your tax renewal requirements to keep your Certificate of Registration or License valid and maintain your compliance.

4. Complete Your Illinois LLC Tax Obligations

Once officially formed, your LLC must comply with state and federal tax requirements. These are based on your tax classification and business activities.

At the federal level, the IRS will tax your LLC as follows:

• Single-member LLCs: These are treated as Disregarded entities. Business income is reported on the LLC owner’s personal return.
• Multi-member LLCs: These are treated as partnerships. Profits pass to LLC members.
• Elected taxation: You can elect to be taxed as a C-Corporation or an S-Corporation.

You may need to pay local and state taxes in addition to your federal taxes. This depends on your operating location and business activities.

Key Contact Information For The Illinois State Agency

You can contact the following state agencies using the information below if you have questions regarding your LLC filings, formation procedures, taxes, or ongoing compliance obligations.

1. Illinois Secretary Of State: Department Of Business Services

The Department of Business Services is responsible for foreign and domestic LLCs formed or registered to conduct business in the state.

2. Illinois Department Of Revenue

The Illinois Department of Revenue is responsible for ongoing state tax compliance procedures and Certificates of Registration.

Phone number: 217-782-3336 or 217-524-4772.

Operating hours: 8:00 A.M. to 5:00 P.M., Monday to Friday.

Frequently Asked Question