Illinois Single Member LLC Filing Requirements

Illinois single member LLC filing requirements start with one document and one fee: Articles of Organization (Form LLC-5.5) filed with the Secretary of State, along with a $150 formation fee.¹ After that, the LLC has to keep a registered agent in the state, file a $75 annual report each year, and report its income on your personal state and federal tax returns. Miss the annual report and the state can dissolve the company.

Filing the Articles of Organization

The Articles of Organization is the document that brings your LLC into legal existence. Illinois uses Form LLC-5.5, which you can complete through the Secretary of State’s online portal or download and mail to the Department of Business Services in Springfield.¹

The form asks for:

The LLC’s name and principal office address. The principal office can be inside or outside Illinois.
A statement of purpose. Most owners use a general-purpose clause covering any lawful activity.
The name and Illinois street address of your registered agent.
Confirmation that the LLC has at least one member at the time of filing.
The name and business address of each manager, or of any member with manager-level authority. This is where you indicate whether the company is member-managed or manager-managed.
Duration. It defaults to perpetual unless you name an end date.
The organizer’s name, address, and signature.

You can pick an effective date later than the filing date, but not more than 60 days out.²

The filing fee is $150. Expedited processing costs an additional $100.¹ Online filers pay by credit card and get a digital receipt immediately. Once the Secretary of State processes the filing, you receive a stamped copy of the Articles. That stamped copy is your primary proof the LLC exists, and banks, licensing agencies, and vendors will all ask for it.

Name Rules

The name has to include “Limited Liability Company,” “L.L.C.,” or “LLC,” and it cannot include terms that suggest a different structure, such as “Corporation,” “Corp.,” “Incorporated,” “Inc.,” “Ltd.,” or “Limited Partnership.”³ It also has to be distinguishable from every other entity already on file with the Secretary of State. Check availability through the Secretary of State’s business name database before filing. If you want to hold a name before you’re ready to file, you can reserve it for $25.¹

Registered Agent

Every Illinois LLC has to continuously maintain a registered agent and a registered office in the state. The agent accepts service of process, subpoenas, and government notices on the LLC’s behalf.⁴

The agent must be either an Illinois resident or a business authorized to operate in the state, and the registered office needs a physical street address. A P.O. Box does not qualify. You can serve as your own registered agent if you have an Illinois address, but your home address becomes part of the public record and you need to be reachable at that address during normal business hours.

Annual Report

Every Illinois LLC has to file an annual report to stay in good standing. The report confirms basic information the state already has: the LLC’s name, principal office address, registered agent details, and the names and addresses of managers or authorized members.⁵

The filing window opens 60 days before the first day of your LLC’s anniversary month, and the report must reach the Secretary of State before the first day of that anniversary month. If your LLC was formed in September, that means filing between early July and September 1. A mailed report counts as timely if postmarked within the window. The filing fee is $75.⁶ Expedited processing runs an additional $50.¹

If You Miss the Deadline

A late annual report triggers a delinquency penalty on top of the $75 fee.⁶ If the delinquency continues, the Secretary of State can administratively dissolve the LLC. A dissolved LLC cannot enforce contracts in its own name, can lose access to business bank accounts, and gives creditors a stronger argument for piercing the liability shield.

Reinstatement is possible but costly. You have to file all past-due annual reports (the state caps this at six years) plus every fee and penalty owed, and the reinstatement filing itself costs $200 on top of that.⁷ Six years of back reports and penalties plus $200 can run over $1,000.

Federal Tax Filings

The IRS treats a single-member LLC as a “disregarded entity” by default. The LLC does not file a separate federal income tax return. Instead, its income and expenses flow to your personal Form 1040 on Schedule C.⁸ If you’d rather have the LLC taxed as a corporation, file Form 8832 with the IRS to elect that treatment.

A single-member LLC with no employees and no excise tax liability is not technically required to obtain an Employer Identification Number, and can use your Social Security number for federal tax purposes. In practice, most banks require an EIN to open a business account, and many vendors and clients ask for one before paying you. Applying through the IRS website is free.⁸

Illinois Tax Filings

Illinois follows the federal treatment. Because the IRS disregards a single-member LLC, Illinois does too, and the LLC has no separate Illinois income tax filing requirement.⁹ The income shows up on your personal Form IL-1040 at the state’s flat rate.

Two situations add filings. If your LLC collects sales tax, you register with the Illinois Department of Revenue and file returns on the schedule the Department assigns. If you have employees, you register for withholding and unemployment insurance. Self-employment tax (Social Security and Medicare) also applies to your LLC earnings at the federal level, whether or not you take formal draws from the business.

Operating Agreement

Illinois law lets LLC members create an operating agreement but does not require one. The statute says members “may enter into an operating agreement” governing the company’s affairs.¹⁰ It is not filed with the state. Even so, a single-member operating agreement is worth having: it documents that the LLC operates independently, which is central to keeping the liability shield intact. Some banks also require a copy before opening a business account in the LLC’s name. It can be created before, at the time of, or after filing the Articles.

At minimum, cover how profits and losses flow to you, what happens if you become incapacitated or die, how the LLC can be dissolved, and your capital contribution.

Recordkeeping

The IRS does not require a specific bookkeeping system, only one that clearly shows income and expenses. Keep records long enough to support the items on your returns; employment tax records must be kept for at least four years.¹¹ Keep the LLC’s money in a dedicated business bank account, and store your Articles of Organization, operating agreement, annual report confirmations, and any amendments together so you can produce them when a bank, agency, or court asks.

1
Illinois Secretary of State. Limited Liability Company Publications and Forms
2
Illinois General Assembly. Illinois Code 805 ILCS 180/5-5 – Articles of Organization
3
Illinois General Assembly. Illinois Code 805 ILCS 180/1-10
4
Illinois General Assembly. Illinois Code 805 ILCS 180/1-35 – Registered Office and Registered Agent
5
Illinois General Assembly. Illinois Code 805 ILCS 180/50-1 – Annual Reports
6
Illinois General Assembly. Illinois Code 805 ILCS 180/50-10
7
Illinois Secretary of State. LLC Reinstatement
8
Internal Revenue Service. Single Member Limited Liability Companies
9
Illinois Department of Revenue. How Does Illinois Tax a Limited Liability Company (LLC)?
10
Illinois General Assembly. Illinois Code 805 ILCS 180/15-5 – Operating Agreement
11
Internal Revenue Service. Recordkeeping