LLC vs DBA in Illinois 2026: Costs, Taxes & Legal Protection
Introduction
If you're starting a business in Illinois, you face a fundamental choice: operate as a sole proprietorship with a DBA (Doing Business As), or form an LLC. Here's the quick answer for most scenarios:
Form an LLC if you have meaningful assets to protect, plan to hire employees, or want professional credibility. You'll pay $150 upfront and $75 annually, but you'll gain personal liability protection and clearer tax options.
Use a DBA if you're testing a business idea with minimal startup capital, operating solo with low risk, and want the absolute lowest compliance burden. You'll pay $120 for the DBA filing, but you'll have zero liability protection and must file personal income taxes on all profits.
The decision hinges on three factors: liability exposure, tax flexibility, and growth plans. Let's break down the numbers.
FAQ: Three Practical Comparison Questions
1. How much does each option actually cost to start and maintain?
LLC Formation: $150 filing fee (805 ILCS 180/5-5) plus $75 annual report fee due before your anniversary month each year (805 ILCS 180/50-1). If you need a DBA for your LLC—which Illinois requires if you operate under a name other than your legal LLC name—add $120. Total first-year cost: $345. Year two and beyond: $75 annually.
DBA Formation: $120 filing fee with the Illinois Secretary of State for assumed names, or with your county clerk if you're a sole proprietor. No annual renewal required for the DBA itself. However, sole proprietors must register for Illinois business tax through MyTax Illinois. Total first-year cost: $120. Ongoing cost: $0 unless you renew or change the name.
Winner for cost: DBA is cheaper upfront ($120 vs $345), but the gap narrows after year two when the LLC's $75 annual fee becomes routine.
2. What's the tax difference between an LLC and a DBA?
DBA (Sole Proprietorship): You report all business income on your personal Form 1040, Schedule C. Illinois taxes individual income at 4.95% (35 ILCS 5/). You also owe self-employment tax (15.3% combined federal rate on 92.35% of net profit). No flexibility—the tax treatment is fixed.
LLC (Default Single-Member): Treated as a disregarded entity for federal tax purposes (Schedule C), so the tax result mirrors a DBA. However, you can elect to be taxed as an S corporation or C corporation. An S corp election can save 15.3% self-employment tax on distributions above a reasonable salary, but requires payroll setup and additional filings. Illinois does not impose a separate LLC income tax; instead, LLCs taxed as partnerships owe 1.5% replacement tax on Illinois-taxable income.
Multi-Member LLC: Taxed as a partnership by default (Form 1065). Each member reports their share on personal returns. Again, you can elect S corp or C corp treatment. The 1.5% replacement tax applies to partnerships.
Winner for tax flexibility: LLC wins decisively. You can optimize your tax structure as your business grows; a DBA locks you into self-employment tax.
3. What liability protection do you actually get?
DBA (Sole Proprietorship): Zero liability protection. Your personal assets (home, car, savings) are exposed to business debts and lawsuits. If a customer sues or you default on a business loan, creditors can pursue your personal property.
LLC: Full liability protection under 805 ILCS 180/. The LLC is a separate legal entity. Creditors can only reach LLC assets, not your personal property. This protection applies even if you're the sole member. The one exception: you remain personally liable for your own negligence or misconduct (e.g., if you cause an accident while performing services).
Winner for protection: LLC provides essential legal separation; DBA offers none.
Side-by-Side Comparison Table
| Dimension | LLC | DBA (Sole Proprietorship) |
|---|---|---|
| Formation Cost | $150 filing fee (805 ILCS 180/5-5) | $120 filing fee |
| Annual Cost | $75 annual report (805 ILCS 180/50-1) | $0 (no renewal required) |
| First-Year Total | $345 (including $120 DBA if needed) | $120 |
| Liability Protection | Full (separate legal entity, 805 ILCS 180/) | None (personal liability) |
| Default Tax Treatment | Disregarded (single-member) or Partnership (multi-member) | Sole proprietorship (Schedule C) |
| Tax Election Options | S corp, C corp available | None |
| Illinois Income Tax Rate | 4.95% (35 ILCS 5/) | 4.95% (35 ILCS 5/) |
| Self-Employment Tax | Yes (unless S corp elected) | Yes (15.3% combined) |
| Annual Compliance | Annual report required | None required |
| Registered Agent Required | Yes (805 ILCS 180/1-35) | No |
| Processing Time | ~10 business days (standard) | Varies by county |
| Name Designator Required | LLC, L.L.C., or Limited Liability Company | None |
Formation Requirements and Process
An LLC requires filing Articles of Organization with the Illinois Secretary of State, Department of Business Services, Limited Liability Division. A DBA requires only a name registration with either the Secretary of State (for LLC assumed names) or your county clerk (for sole proprietorships). LLCs demand specific organizational details; DBAs do not.
LLC Articles of Organization must include (805 ILCS 180/5-40):
- LLC name with required designator (LLC, L.L.C., or Limited Liability Company)
- Principal place of business address
- Registered agent name and address
- Organizer name, address, and signature
- Effective date (you can delay this)
- Manager or member information
- Purpose statement (optional but recommended)
DBA registration requires only:
- Business name
- Owner name and address
- Filing location (county clerk or Secretary of State)
You can file an LLC online through the Illinois Secretary of State portal (https://apps.ilsos.gov/llcarticles/index.jsp). DBA filing varies by county—some accept online submissions, others require paper forms mailed to the county clerk.
Which is better for this dimension: LLC requires more upfront work but establishes a legal entity; DBA is simpler but doesn't create a separate business structure.
Filing Fees and Costs
An LLC costs $150 to file with the Illinois Secretary of State under 805 ILCS 180/5-5. A DBA costs $120 when filed with the Secretary of State for an LLC assumed name. If you're a sole proprietor filing a DBA with your county clerk, fees vary by county (typically $50–$150). The LLC fee is higher because you're creating a legal entity, not just registering a name.
| Cost Element | LLC | DBA |
|---|---|---|
| Standard Filing Fee | $150.00 (805 ILCS 180/5-5) | $120.00 (Secretary of State for LLC assumed names) |
| Expedited Filing Fee | +$100.00 (24-hour service) | Not available |
| Series LLC Setup | $400.00 + $100.00 expedited fee | N/A |
| Name Reservation Fee | $25.00 (90-day hold) | Included in DBA filing |
| Registered Agent Change | $25.00 | N/A |
| Annual Report Fee | $75.00 (due before anniversary month, 805 ILCS 180/50-1) | Not required |
| Late Annual Report Penalty | $100.00 (after 60 days delinquent) | N/A |
First-year cost comparison:
- LLC with DBA: $150 + $120 + $75 = $345
- DBA alone: $120
- LLC without DBA (using legal name): $150 + $75 = $225
Which is better for this dimension: DBA is cheaper upfront ($120 vs. $150), but LLCs require ongoing annual report fees ($75/year); a DBA has no recurring costs.
Processing Time and Effective Date
Standard LLC formation takes approximately 10 business days for online filings with the Illinois Secretary of State. You can expedite to 24 hours by paying an additional $100 fee. You control the effective date—you can file today but make the LLC effective 30 days from now (805 ILCS 180/5-5). DBA processing times vary by filing location. The Secretary of State typically processes faster than individual county clerks, but exact timelines are not standardized.
| Timeline | LLC | DBA |
|---|---|---|
| Standard Processing | ~10 business days (online filing) | Varies by county clerk or Secretary of State |
| Expedited Processing | 24 hours (+$100 fee) | Not available |
| Effective Date Control | Yes, you can choose a delayed effective date (805 ILCS 180/5-5) | Typically effective upon filing |
| Filing Confirmation | Immediate online confirmation | Varies |
Which is better for this dimension: LLC offers predictable timelines and expedited options; DBA processing depends on your county's backlog.
Liability Protection and Legal Status
An LLC creates a separate legal entity that shields your personal assets from business debts and lawsuits. Illinois law provides standard charging order protection under 805 ILCS 180/. A DBA provides no liability protection—you remain personally liable for all business obligations. This is the fundamental distinction: an LLC separates you from your business; a DBA does not.
LLC Liability Protection (805 ILCS 180/):
- Members are not personally liable for LLC debts or obligations
- Creditors can only pursue LLC assets, not member personal property
- Protection applies even if you're the sole member
- Exception: You remain liable for your own negligence or misconduct
- Charging order is the exclusive remedy for creditors (805 ILCS 180/15-108)
DBA Liability Exposure:
- No separation between personal and business liability
- Creditors can pursue your personal assets (home, car, savings)
- You're personally liable for all business debts
- Lawsuits can target your personal property
- No legal protection if the business fails
Real-world example: If your LLC is sued for $50,000 and loses, creditors can only claim LLC assets. Your personal home is protected. If your DBA is sued for the same amount, creditors can seize your personal property to satisfy