Is an operating agreement required for Illinois LLCs?

This page has not confirmed whether Illinois law requires an LLC to have an operating agreement, so it does not answer yes or no. A written agreement signed by every member is worth having either way. It records who owns what share of the LLC, who makes decisions, and how profits are divided. To learn what Illinois requires, check the website of the state agency that registers LLCs in Illinois, or ask a business attorney licensed in Illinois.

Can I write my own Illinois LLC operating agreement?

Yes, you can write your own Illinois LLC operating agreement. It should cover each member's ownership share, voting rights, how profits are divided and how the LLC is closed down, because the default rules in Illinois's LLC law can apply where the agreement is silent. Read the guidance for LLCs on the website of the state agency that registers them in Illinois, and consider having a business attorney licensed in Illinois review your draft before the members sign it.

Does an Illinois LLC operating agreement need to be notarized?

This page has not confirmed whether Illinois law asks for an operating agreement to be notarized. Have every member sign and date it and keep it with the LLC's records. A bank or lender may ask for notarized signatures, so ask before you sign.

What happens if my Illinois LLC doesn't have an operating agreement?

Without an operating agreement, members have no written terms to settle a disagreement. Where the members have no agreement on a point, the default rules in Illinois's LLC law can apply instead. Read the guidance for LLCs on the website of the state agency that registers them in Illinois before you draft the agreement.

Can I amend my Illinois LLC operating agreement later?

Yes. An operating agreement can be changed by following the amendment procedure it sets out, such as a vote or the written consent of the members it names. If the agreement says nothing about amendments, the default rules in Illinois's LLC law can apply, so check them, or ask an Illinois business attorney, before you change a term. Put each amendment in writing, have the members sign it, and keep it with the agreement. To amend the LLC's Articles of Organization on file with the state, Illinois uses a separate filing, the Articles of Amendment.

Illinois LLC Operating Agreement: What to Include

What to put in an operating agreement for your Illinois LLC, and how single-member and multi-member agreements differ.

By Edmond Hui · Last updated: October 2026

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Key sections of an Illinois LLC operating agreement, listing the 7 provisions the document should cover. — What an Illinois operating agreement should contain, section by section. Source: Illinois Secretary of State.

Watch: Illinois LLC Operating Agreement: What to Include (2026)

What to Include in Your Operating Agreement

Ownership & membership

Define each member's ownership percentage and capital contributions. This section establishes who owns what portion of the LLC and prevents future disputes.

Management structure

Specify whether your Illinois LLC is member-managed or manager-managed. This determines who has authority to make business decisions and bind the company.

Voting rights

Outline how decisions are made, including voting procedures and what percentage of votes are needed for different types of decisions. This ensures smooth operations and prevents deadlock.

Profit/loss allocation

Detail how profits and losses will be distributed among members and when distributions will be made. This section matters for tax reporting and member expectations.

Member duties

Define the responsibilities, rights, and obligations of each member. This includes management duties, financial obligations, and any restrictions on member activities.

Dissolution process

Establish the procedures for dissolving the LLC, including triggering events and asset distribution. This protects all members' interests if the business ends.

Amendment procedures

Set forth how the operating agreement can be modified in the future. This ensures changes can be made legally and with proper member consent.

Read this guide for another state:

Frequently Asked Questions

: This page has not confirmed whether Illinois law requires an LLC to have an operating agreement, so it does not answer yes or no. A written agreement signed by every member is worth having either way. It records who owns what share of the LLC, who makes decisions, and how profits are divided. To learn what Illinois requires, check the website of the state agency that registers LLCs in Illinois, or ask a business attorney licensed in Illinois.
: Yes, you can write your own Illinois LLC operating agreement. It should cover each member's ownership share, voting rights, how profits are divided and how the LLC is closed down, because the default rules in Illinois's LLC law can apply where the agreement is silent. Read the guidance for LLCs on the website of the state agency that registers them in Illinois, and consider having a business attorney licensed in Illinois review your draft before the members sign it.
: This page has not confirmed whether Illinois law asks for an operating agreement to be notarized. Have every member sign and date it and keep it with the LLC's records. A bank or lender may ask for notarized signatures, so ask before you sign.
: Without an operating agreement, members have no written terms to settle a disagreement. Where the members have no agreement on a point, the default rules in Illinois's LLC law can apply instead. Read the guidance for LLCs on the website of the state agency that registers them in Illinois before you draft the agreement.
: Yes. An operating agreement can be changed by following the amendment procedure it sets out, such as a vote or the written consent of the members it names. If the agreement says nothing about amendments, the default rules in Illinois's LLC law can apply, so check them, or ask an Illinois business attorney, before you change a term. Put each amendment in writing, have the members sign it, and keep it with the agreement. To amend the LLC's Articles of Organization on file with the state, Illinois uses a separate filing, the Articles of Amendment.

Sources

3 documents

Each entry below is a document recorded in our verified Illinois sources, and each entry says what the document is. Some statutory text is read from an accurate mirror rather than from the state's own host, and those say so. Where we hold the citation but no stable public link, the citation is printed on its own rather than pointed at a guessed address.

Illinois statute: 805 ILCS 180 (LLC Act)
Illinois statute: 805 ILCS 180/ (LLC Act)
ilsos.gov/departments/business-services/limited-liability-companies.htmlIllinois Secretary of State: business entity filings

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Edmond Hui · Founder, MyStateLLC

Edmond Hui is a software engineer and serial entrepreneur based in New York who has founded multiple online businesses across e-commerce, media, and information publishing. Before transitioning into tech, he spent years as a commercial real estate professional closing deals totaling over 100,000 square feet, giving him firsthand experience with business formation and entity structuring. He built MyStateLLC to provide the free, state-specific LLC guidance he wished existed when forming his own companies.

How we check facts

What to Include in Your Operating Agreement

Ownership & membership

Management structure

Voting rights

Profit/loss allocation

Member duties

Dissolution process

Amendment procedures

Frequently Asked Questions

Sources

More for Illinois LLCs

Start and set up

Taxes, money and growth

Stay compliant

Operate in other states

Compare structures

By owner type

By profession

Ready to Form Your Illinois LLC?

More Illinois LLC Guides

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