Does an LLC need an assumed name in Illinois?

Illinois requires an LLC that does business under a name other than its own to register an assumed name. File before the LLC starts doing business under the assumed name.

DBA · Illinois

How to File an Assumed Name for an LLC in Illinois

By Edmond Hui · Last updated October 7, 2026

Short answer

Illinois requires an LLC that does business under a name other than its own to register an assumed name. An LLC files the Application to Adopt, Change, or Cancel an Assumed Name with the Secretary of State. File before the LLC starts doing business under the assumed name.

Illinois Assumed Name at a Glance

Requirement: Required
Where to file: Secretary of State
Fee: See Cost and renewal
How long it lasts: 5 years
Newspaper notice: None found
File online: Yes

How an LLC Files

File before the LLC starts doing business under the assumed name.

An LLC files the Application to Adopt, Change, or Cancel an Assumed Name with the Secretary of State.

Filing needs the LLC in active status on the state's records. This applies to filing online, which the Secretary of State offers to LLCs in good standing. No source read sets the same condition for a paper filing.

You can file online.

Open the filing office's site · Open the filing page

Cost and Renewal

The filing fee is $150.00. The $150 fee applies when you file in a year ending in 0 or 5 and drops by $30 for each later year of the five year cycle, to $30 in a year ending in 4 or 9. A five year renewal costs $150, and a payment processor fee is added online.

The registration has a 5-year term.

The right to use the name runs from filing until the first day of the LLC's anniversary month in the next calendar year evenly divisible by five. It is renewed for five years on the annual report, within the 60 days before it expires.

Renewal costs $150.00.

Publication

We found no publication step for an LLC's assumed name filing in Illinois.

If you skip it

An LLC that puts up a sign or advertisement under a name other than its own or an adopted assumed name commits a petty offense with a fine of $501 to $1,000, and each day counts again.

Sole proprietors

Illinois requires a sole proprietor who does business under a name other than their legal name to register an assumed name. The rule covers an individual or general partnership, and moving to or adding a location in another county needs a new certificate and publication there. An individual or partnership that trades under an assumed name without filing commits a Class C misdemeanor, with each day a separate offense.

A sole proprietor registers an assumed name with the county clerk in each county where the business operates.

Filing needs acknowledgment before a clerk or notary.

The state sets a default of $5.00, which each county may change. State law sets a $5 county clerk fee for filing and indexing the certificate, and a county board may raise it by ordinance after a cost study. Ask your county clerk for the current fee, and expect the newspaper to charge separately for publication.

After filing, you must publish notice of the filing in a newspaper of general circulation published in the county where the certificate is filed, once a week for 3 consecutive weeks. The first notice must run within 15 days after the certificate is filed. Proof of publication must be filed with the county clerk within 50 days after the certificate is filed, or the certificate is void.

Requirement	Required
Where to file	County office (county clerk)
Fee	Varies by county
How long it lasts	Not confirmed
Newspaper notice	Required
File online	Not confirmed

Next steps

Frequently Asked Questions

: Illinois requires an LLC that does business under a name other than its own to register an assumed name. File before the LLC starts doing business under the assumed name.
: An LLC files the Application to Adopt, Change, or Cancel an Assumed Name with the Secretary of State. Filing needs the LLC in active status on the state's records. This applies to filing online, which the Secretary of State offers to LLCs in good standing. No source read sets the same condition for a paper filing.
: The filing fee is $150.00. The $150 fee applies when you file in a year ending in 0 or 5 and drops by $30 for each later year of the five year cycle, to $30 in a year ending in 4 or 9. A five year renewal costs $150, and a payment processor fee is added online.
: The registration has a 5-year term. The right to use the name runs from filing until the first day of the LLC's anniversary month in the next calendar year evenly divisible by five. It is renewed for five years on the annual report, within the 60 days before it expires. Renewal costs $150.00.
: We found no publication step for an LLC's assumed name filing in Illinois.
: An LLC that puts up a sign or advertisement under a name other than its own or an adopted assumed name commits a petty offense with a fine of $501 to $1,000, and each day counts again.
: Illinois requires a sole proprietor who does business under a name other than their legal name to register an assumed name. The rule covers an individual or general partnership, and moving to or adding a location in another county needs a new certificate and publication there. An individual or partnership that trades under an assumed name without filing commits a Class C misdemeanor, with each day a separate offense. A sole proprietor registers an assumed name with the county clerk in each county where the business operates.

This guide is general information, not legal or tax advice, and reading it does not create an attorney-client relationship. It reports what each state's filing office publishes about registering a business name, with the sources this page cites. A filing here does not register a federal trademark, and fees and forms change between our reviews. Confirm with the office named on this page before you file.

Sources

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.

ilga.gov/legislation/ilcs/ilcs3.asp?ActID=2299&ChapterID=65Illinois Assumed Business Name Act, 805 ILCS 405
ilga.gov/legislation/ilcs/fulltext.asp?DocName=080501800K1-20Illinois Limited Liability Company Act, 805 ILCS 180/1-20 (Assumed name)
ilga.gov/legislation/ilcs/fulltext.asp?DocName=080501800K50-10Illinois Limited Liability Company Act, 805 ILCS 180/50-10 (Fees)
ilga.gov/legislation/ilcs/fulltext.asp?DocName=005500050K4-4001Illinois Counties Code, 55 ILCS 5/4-4001 (County clerks; counties of first and second class)
ilga.gov/legislation/ilcs/fulltext.asp?DocName=005500050K4-12003Illinois Counties Code, 55 ILCS 5/4-12003 (Fees of county clerk in third class counties)
ilsos.gov/departments/business-services/assumed-name-adoptions/llcinstructions.htmlIllinois Secretary of State, Adopting an Assumed LLC Name
ilsos.gov/content/dam/publications/pdf_publications/llc120.pdfIllinois Form LLC-1.20, Application to Adopt, Change, or Cancel an Assumed Name
ilga.gov/legislation/ilcs/ilcs3.asp?ActID=2299&ChapterID=65Assumed Business Name Act (805 ILCS 405), section 1

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.