Illinois Secretary of State Business Search

Last Updated on January 30, 2024

Illinois state map

The Secretary of State of Illinois maintains a database that contains information on hundreds of thousands of business entities, primarily including Corporations, Limited Liability Companies (LLCs), Limited Companies (LC), Limited Partnerships (LP), and Limited Liability Partnerships (LLP).

The business database also has information regarding the following types of entities:

  • Corporation
  • Not-for-Profit Corporation
  • Limited Partnership
  • Limited Company
  • Limited liability Company

See: How to start an LLC in Illinois

Sole proprietorships and partnerships do not register their business with the Secretary of State. They can register their business name, however, the name is registered with the County Clerk’s office in the county where the business is located by filing an Assumed Name Notice.

How to do an Illinois SOS Business Entity Search

To do your search for a business entity or to search for corp or LLC name availability, you need to know to have at least one of the following information with you:

  • Name
  • Keyword
  • Partial Word
  • File Number

To make your business name search easier, we have created an easy-to-follow guide for you below.

Step 1 – To do an Illinois business search, visit the Illinois Secretary of State Division of Corporations website (it will look like the screenshot below).

illinois business entity and corporation search

Step 2 – Choose what type of business entity you are searching for. In this example, we’ve selected “Corporate and LLC.”

Illinois search by entity name

Step 3 – Next, choose any of the search methods provided. In this example, we’ve chosen to search by name.

Step 4 – Now enter the Business Entity name in the field. For our sample name, let us type in “Exelon,” then click the “Submit” button.

Business entity search result

Step 5 – The Results Page will then appear (see the screenshot below for reference).

Company Details

Click on the business entity’s name to access detailed information about the entity, including its:

  • Legal Name
  • Status
  • Entity Type (Corporation, Limited Liability Company, etc.)
  • Registered Agent Information
  • Annual Report Filing Date
  • File Number
  • State of Formation (If the result is Illinois, it is a domestic entity, while an out-of-state result is a foreign entity)
  • Officer Information

Here, you can also request a certificate of good standing.

Information on the Illinois Secretary of State’s Office

Illinois sos seal


As the second largest constitutional office of the state, the Secretary of State of Illinois is also an elected governmental institution.

The Secretary of State of Illinois is a government office visited by more Illinois residents than any other government office in the state.

Alex Giannoulias is the Illinois Secretary of State. 


The Secretary of State of Illinois is the custodian of the public records, Illinois UCC filings and archives, state laws, state records, State Capitol and Library. Aside from registering corporations, lobbyists, and notaries, he is also in charge of issuing licenses to Illinois-registered vehicles and motorists.

Secretary of State Contact Information

213 State Capitol
Springfield, IL 62756

State Business Name Search Instructions

Can I reserve an LLC name in Illinois?

​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​If there is a name that you want to use for your LLC, but you aren’t ready to form an LLC, you can file the Name Reservation Form. A name can be held for up to 90 days by filing the form and paying a $25 filing fee with the Illinois Secretary of State, Business Services.

Where can you find information on Illinois business licenses?

The business name registration is different from business licensing in Illinois. Many business licenses are issued at the local level and are not searchable. Some services are regulated in the state and require licensing from the Illinois Department of Financial & Professional Regulation and these can be searched.

Another business registration that isn’t a business license, but is commonly needed is the Employer Identification Number (EIN). The EIN is available at no cost from the Internal Revenue Service (IRS).

What is a registered agent?

In Illinois, one of the requirements for a corporation or LLC is that a Registered Agent has to be named.  This agent is a single point of contact in case the business needs to be served with legal papers or contacted by the state. One of the business owners often files as the entity's Registered Agent. When they file, their home address is often used (PO Boxes aren’t allowed), and the owner's name and address are now a public record that can be looked up by anyone. This can be a big concern, especially for home-based businesses. Using a commercial Registered Agent service like Northwest Registered Agent will keep their personal address from being public record.

How much does it cost to do a business search in Illinois?

There is no cost to search for businesses using the Illinois business search database.