L
LexiState
dba guideUpdated 2026-03-31

How to File a DBA in Illinois

Where to File Your DBA in Illinois

Filing location depends entirely on your business structure. Sole proprietors file at the county level: you submit your DBA application to the county clerk or recorder in the county where your business operates. LLCs file with the state: assumed names for LLCs are filed with the Illinois Secretary of State, Department of Business Services, Limited Liability Division, not at the county level. This is a critical distinction—filing in the wrong location will delay or invalidate your registration.

Filing Location Depends on Your Business Structure

Your DBA filing location in Illinois depends on whether you operate as a sole proprietorship or an LLC. Sole proprietors file at the county level, while LLC owners file with the Illinois Secretary of State. Understanding this distinction ensures your assumed name gets registered in the correct place and remains legally valid.

For Sole Proprietorships: County Clerk or Recorder

If you operate as a sole proprietor, you file your DBA with the county clerk or recorder in the county where your business operates. Illinois requires sole proprietors to register a DBA, and county-level filing is the only option for this business structure.

Contact your county clerk's office directly for current fees, processing times, and submission methods. Requirements vary by county, so confirm local procedures before filing.

For LLCs: Illinois Secretary of State

If you've formed an LLC, you file your assumed name (DBA) with the Illinois Secretary of State, Department of Business Services, Limited Liability Division, not at the county level. Unlike sole proprietors, LLC owners submit assumed-name adoptions to the state-level Limited Liability Division. This is a critical difference from sole proprietorship rules.

You can file online through the Secretary of State's LLC assumed-name portal or submit a paper form. The current filing fee is $120 for 2026.

Online Filing for LLCs

The fastest way to file your LLC's assumed name is through the Secretary of State's online system at https://apps.ilsos.gov/llcarticles/index.jsp. Non-expedited review takes about 10 days, while expedited review (available for an additional fee) takes about 24 hours.

You can also file by mail or in person at either Secretary of State office:

  • Springfield: 501 S. Second St., Rm. 350, Springfield, IL 62756
  • Chicago: 69 W. Washington St., Ste. 1240, Chicago, IL 60602

Call (217) 524-8008 if you have questions about the filing process.

How Long Your DBA Remains Valid

Your LLC's assumed name remains effective until the first day of your company's anniversary month in the next calendar year evenly divisible by five. After that, the name renews automatically for five-year periods, provided you pay the renewal fee when due.

For example, if you file in 2026, your assumed name is valid through the first day of your anniversary month in 2030, then renews for another five-year period.

Before You File: Search for Name Availability

Before filing your DBA, search the Secretary of State's business entity database at https://apps.ilsos.gov/businessentitysearch/ to confirm your assumed name isn't already in use. Your assumed name must be distinguishable from existing domestic and foreign LLCs, corporations, and other registered names on file.

If you want to reserve a name before filing your articles, you can reserve it for 90 days for a $25 fee.

What You Need to Know About Illinois DBA Requirements

Illinois requires both sole proprietors and LLCs to register a DBA if they operate under a name other than their legal business name. For sole proprietors, this means filing at the county level. For LLC owners, the Secretary of State handles all assumed-name filings—not your county clerk.

Make sure you file in the correct location for your business structure to avoid delays or rejection.

DBA Filing Fees in Illinois

For LLCs filing an assumed name with the Secretary of State, the 2026 fee is $120. Illinois uses a tiered fee schedule based on the calendar year. Since 2026 ends in "6," the fee is $120. This fee applies to initial assumed-name adoptions. The fee schedule varies: $150 for years ending in 0 or 5; $120 for years ending in 1 or 6; $90 for years ending in 2 or 7; $60 for years ending in 3 or 8; and $30 for years ending in 4 or 9.

For sole proprietors filing at the county level, fees vary by county. Illinois does not set a statewide DBA filing fee for county-level registrations. Contact your county clerk's office directly for the exact fee in your jurisdiction, as costs differ across Illinois counties.

Cost of Filing a DBA in Illinois

Illinois charges $120.00 to file a DBA (assumed name) for an LLC with the Secretary of State. The fee applies when you adopt an assumed name for your limited liability company. If you operate as a sole proprietor, you file your DBA at the county clerk or recorder in the county where your business operates—county fees vary by location.

Where You File and What Determines the Fee

Your filing location depends on your business structure. LLC owners file assumed names with the Illinois Secretary of State, Department of Business Services. Sole proprietors file DBAs only at the county clerk or recorder in their operating county. The $120.00 fee applies exclusively to LLC assumed-name filings with the state.

Fee Schedule by Year

Illinois uses a five-year renewal cycle for LLC assumed names. Your adoption fee depends on the calendar year in which you file:

  • $150 for years ending in 0 or 5
  • $120 for years ending in 1 or 6
  • $90 for years ending in 2 or 7
  • $60 for years ending in 3 or 8
  • $30 for years ending in 4 or 9

For 2026, the fee is $120. Your assumed name remains effective until the first day of your LLC's anniversary month in the next calendar year evenly divisible by five, then renews automatically for five-year periods.

Processing Time and Expedited Options

Standard review takes about 10 business days. If you need faster approval, Illinois offers expedited review in about 24 hours for an additional fee—check with the Secretary of State for the current expedited-service charge.

How to File Your DBA

File online through the Illinois Secretary of State's LLC assumed-name portal at https://www.ilsos.gov/departments/business-services/assumed-name-adoptions/llcinstructions.html. You can also file in person or by mail at:

  • Springfield office: 501 S. Second St., Rm. 350, Springfield, IL 62756
  • Chicago office: 69 W. Washington St., Ste. 1240, Chicago, IL 60602

Call (217) 524-8008 with questions about your filing.

Important Notes for Sole Proprietors

If you operate as a sole proprietor, you do not file with the Secretary of State. Instead, contact your county clerk or recorder to learn local DBA filing requirements and fees. Illinois requires sole proprietors to obtain a DBA before operating under a name other than their legal name.

What Information You Must Include

Filing location depends on your business structure. For sole proprietorships, you file your DBA (assumed name) with the county clerk or recorder in the county where your business operates. For LLCs, you file assumed names with the Illinois Secretary of State, not at the county level. This distinction is critical—filing in the wrong location will delay your assumed-name protection.

Required Information for Sole Proprietorship DBAs

When filing a DBA as a sole proprietor at your county clerk's office, you must provide:

  • Your legal name
  • The assumed business name you plan to use
  • Your business address in the county
  • The county where you're filing
  • Your signature

Contact your specific county clerk's office for exact form requirements, as counties may have additional local filing instructions beyond state requirements.

Required Information for LLC Assumed Names

If your LLC is filing an assumed name with the Illinois Secretary of State, you must include:

  • Your LLC's legal name (as registered with the Secretary of State)
  • The assumed name you want to adopt
  • Your LLC's principal place of business address
  • The effective date (if you want a future start date)

File through the Illinois Secretary of State's online portal at https://apps.ilsos.gov/llcarticles/index.jsp or submit Form LLC-5.6 by mail to the address listed on the Secretary of State website.

Filing Fees and Timeline

For sole proprietorship DBAs: Contact your county clerk for the filing fee, as counties set their own rates.

For LLC assumed names: The 2026 filing fee is $120. Processing takes approximately 10 days for standard review or 24 hours for expedited service (expedited service costs an additional fee).

Your assumed name remains effective until the first day of your LLC's anniversary month in the next calendar year evenly divisible by five, then renews automatically for five-year periods.

Name Availability Check Before Filing

Before submitting your DBA, search the Illinois Secretary of State's business entity database at https://apps.ilsos.gov/businessentitysearch/ to confirm your assumed name is available. This search covers existing DBAs, LLCs, corporations, and reserved names.

For sole proprietorships, also contact your county clerk to verify the name hasn't been registered locally in your county.

Contact Information for Filing Questions

Illinois Secretary of State, Department of Business Services:

  • Phone: (217) 524-8008
  • Address: 501 S. Second St., Rm. 350, Springfield, IL 62756 or 69 W. Washington St., Ste. 1240, Chicago, IL 60602
  • Website: https://www.ilsos.gov/

For sole proprietorship DBAs: Contact your county clerk's office directly for filing procedures and fees specific to your county.

DBA Expiration and Renewal in Illinois

For LLC assumed names filed with the Secretary of State, the registration remains effective until the first day of the company's anniversary month in the next calendar year evenly divisible by five. This means if you file an assumed name in 2026, it expires on the first day of your LLC's anniversary month in 2030

Related Pages