Illinois Business Search

A field guide to the public business registry, written beside the official search.

Illinois Business Search

Illinois assumed name

Quick answer. An Illinois LLC that wants to operate under a name other than its legal name files an assumed-name adoption with the Secretary of State. The legal entity is still found by its real name or file number in the business entity search. A sole proprietor’s assumed name is a different, often county-level, filing.

Official office

Illinois Secretary of State, Department of Business Services

Open the official search

Phone: (217) 782-6961

501 S. Second Street, Springfield, IL 62756

Monday–Friday, 8:00 a.m.–4:30 p.m. Central. LLC annual-report questions: (217) 524-8008. Chicago office: 69 W. Washington Street, Suite 1240, (312) 793-3380.

Steps

  1. Look up the legal entity first

    Search the LLC or corporation in the entity search. The assumed name is an additional filing, listed on the Secretary of State’s LLC page as “LLC Assumed Name Adoption” and “LLC Assumed Name Renewal.”

  2. Do not treat the assumed name as a new company

    Contracts, bank accounts, and lawsuits should identify the legal entity and can add “doing business as” the assumed name. Searching only the assumed name and finding nothing does not mean the LLC is fictitious. Search the legal name too.

  3. Renew it on the LLC’s cycle, not whenever you remember

    The LLC page lists assumed-name renewal as its own item, next to the annual report. They are not the same form. Missing one does not automatically file the other.

  4. Know when the county clerk is the right office

    An unincorporated person using a business name is often filing with a county clerk, not with the Secretary of State. If there is no LLC and no corporation, the Springfield entity search will be empty for a reason.

Why the entity search still matters

Lenders and customers search the brand they see on a truck. The brand may be the assumed name. The party who can be paid or sued is the entity on the articles. Ask for both names, then confirm the entity’s status and file number before you wire funds.

Common mistakes

  • Filing an assumed name and believing it created an LLC.
  • Letting the assumed name expire and continuing to invoice under it.
  • Searching only Cook County when the company is an LLC that adopted the name at the state level.

Questions

Where does an Illinois LLC file an assumed name?

With the Illinois Secretary of State, Department of Business Services. The LLC section lists assumed-name adoption and renewal alongside the other LLC filings.

Will the assumed name show up as its own corporation?

No. It is a filing on the entity. Search the legal name or file number to see the company, then look for the assumed-name filing.

Is an assumed name the same as the annual report?

No. The annual report keeps the entity active. The assumed name is permission to use another name. Each has its own form.

Sources reviewed