No.
If you’re a licensed professional in Illinois — attorney, doctor, architect, accountant — you cannot practise through a standard limited liability company. You need a professional limited liability company, a PLLC, and the two are not interchangeable.
This catches people out because almost every guide to forming a business in Illinois is written for businesses generally. Several of them rank well for law firm queries. Follow one and you’ll file the wrong thing.
What follows is what Illinois actually requires, what it costs, and the part most attorneys skip: you aren’t obliged to form anything at all, and there’s a specific reason you should anyway. If you’re working through the whole launch rather than just this question, the full Illinois sequence is here.
In full disclosure: Amata provides office space, virtual offices, business addresses, live reception, and paralegal and administrative support to attorneys, and through Amata Registered Agent, LLC we serve as registered agent too. Several of those turn out to be relevant to the argument below rather than in conflict with it, and I’ll say where.
Can an Illinois attorney form a standard LLC?
No. Illinois has required licensed professionals to use a professional limited liability company since August 2018, and LLCs already in existence were required to amend. A standard limited liability company is simply not an available structure for a law practice in this state, whatever a general business formation guide tells you.
The distinction is more than a letter. A PLLC additionally registers with the Illinois Department of Financial and Professional Regulation, which a standard LLC does not — and IDFPR has been actively enforcing the difference.
If you formed an LLC before 2018 and never amended it, that’s worth checking now rather than when someone asks.
Do you have to form anything at all?
No, and this surprises most attorneys. Illinois does not require you to register a business entity to practise law. A sole proprietorship needs no state filing whatsoever — you’d register an Assumed Name only if you practise under a name other than your own.
Your actual options:
Sole proprietorship. No filing, no fee, no annual report. You and the firm are one legal person.
PLLC. The common choice. Liability separation for business obligations.
Limited liability partnership. For two or more attorneys.
Professional corporation. Older structure, still available, different tax treatment.
Most new solos use a PLLC, and the reason is specific rather than general.
What does it cost to form a PLLC in Illinois?
$200 to start and $75 a year to keep it: $150 for Articles of Organization with the Secretary of State, plus $50 for the IDFPR Certificate of Registration, then a $75 annual report every year after that. An EIN from the IRS is free.
| Step | Form | Cost |
|---|---|---|
| Articles of Organization, Secretary of State | LLC-5.5 | $150 |
| Certificate of Registration, IDFPR | — | $50 |
| Annual report, each year after | LLC-50.1 | $75 |
| EIN | SS-4 | Free |
Expedited processing adds roughly $100 if you’re in a hurry. That $200 sits inside a larger first-year picture — the full arithmetic is here.
The IDFPR step is the one people miss, because the generic Illinois LLC guides don’t mention it. Filing with the Secretary of State alone leaves you with an unregistered professional entity.
Do you need a registered agent?
Only if you form an entity, and you can be your own. Illinois requires a registered agent with a physical street address in the state — a PO box won’t satisfy it. If you’re an Illinois resident with a street address, you can serve as your own agent.
The trade-off is publicity. Your name and address become part of the public record, which for some attorneys is exactly the thing they formed the entity to manage. The same question applies to the address you give the ARDC, covered in the office piece.
This is where the entity question and the address question turn out to be the same question. You need an Illinois street address for the registered agent, a business address for the ARDC master roll, and somewhere for mail and process service to actually arrive.
Those can be one address. For most solos they should be, because three addresses means three places something can go wrong and a process server who can’t find you.
Amata handles all three, which is the second place my disclosure matters. A business address or virtual office covers the ARDC roll and your mail from $69 a month, and Amata Registered Agent, LLC at 33 North Dearborn serves as registered agent — three minutes from the Daley Center, with people in the building during business hours to receive what arrives.
That last part isn’t incidental. A registered agent exists to be found. An address where service of process is handed to an actual person, rather than left against a door, is the whole point of the requirement.
A sole proprietor needs none of this — no agent, no filing, no annual report.
So why form one?
Because as a sole proprietor you are personally liable for every contract your practice signs. The office lease. The equipment agreement. The vendor contracts. The staffing arrangements. There is no separation between you and the firm, because there is no second entity — you are the firm.
Sign a three-year office lease as a sole proprietor and close the practice in year two, and the landlord’s claim is against you. Your savings, your house, your assets.
Sign that same lease through a PLLC and the claim is against the PLLC.
That’s what $200 and a $75 annual report buys, and for most attorneys it’s the easiest decision in the whole launch.
This is where my disclosure matters. Amata leases offices, and our agreements, our reception plans and our staffing programmes are all contracts an attorney signs. I’m on the other side of precisely the thing I’m describing.
I’d still rather you signed ours as a PLLC. A practice that fails and leaves someone’s personal finances intact is one they might rebuild, and I’ve seen that happen more than once.
What a PLLC does not protect you from
Your own malpractice. You remain personally liable for your own professional negligence whatever entity you practise through, and no structure available in Illinois changes that. It is the most common misunderstanding about professional entities and it is worth being blunt about.
The PLLC protects your personal assets from the firm’s business obligations — debts, leases, contracts, and in a multi-attorney firm, the acts of your partners and employees.
It does not protect you from you. If you miss a limitations period, the claim reaches you personally regardless of what’s on your letterhead.
That’s what malpractice insurance is for, which Illinois doesn’t require but which ISBA Mutual reports is the difference between a $28,000 defence bill and someone else paying it. The entity and the insurance are separate decisions solving separate problems, not alternatives.
What about naming the firm?
Illinois permits trade names provided they are not misleading, under Rule 7.5 on firm names and letterheads and the general standard in Rule 7.1. You are not required to practise under your own surname, which surprises attorneys who assume otherwise.
If you use anything other than your own name, a sole proprietor registers an Assumed Name with the county; a PLLC’s name is established in the Articles of Organization.
The constraint is the misleading standard, not the form. A name implying partners you don’t have, or a size you aren’t, is the problem — not a trade name as such.
Frequently asked questions
No. Illinois has required licensed professionals to use a professional limited liability company since August 2018, and existing LLCs were required to amend. A PLLC additionally registers with IDFPR, which a standard LLC does not, and that difference is actively enforced.
A PLLC is restricted to licensed professionals and carries an additional registration with the Illinois Department of Financial and Professional Regulation beyond the Secretary of State filing. A standard LLC has no professional licensing component and is not available to attorneys practising law.
No. Illinois does not require entity formation in order to practise law, and a sole proprietorship needs no state filing at all. Most attorneys form a PLLC anyway, because a sole proprietor is personally liable for every contract the practice signs.
$150 for Articles of Organization with the Secretary of State, $50 for the IDFPR Certificate of Registration, and $75 for the annual report each year afterwards. An EIN from the IRS is free, and expedited processing adds roughly $100 if needed.
No. You remain personally liable for your own professional negligence regardless of entity. A PLLC separates your personal assets from the firm’s business obligations — leases, debts, vendor contracts — and in multi-attorney firms from colleagues’ acts. Insurance covers the rest.
Yes, provided you are an Illinois resident with a physical street address in the state. A PO box will not satisfy the requirement. The trade-off is that your name and home address become public record, and that someone must be present to receive service of process during business hours.
Yes. Amata Registered Agent, LLC provides registered agent service from 33 North Dearborn in the Chicago Loop, three minutes from the Daley Center. The same address can serve as your business address for ARDC registration and for mail and process service.
Illinois required existing LLCs held by licensed professionals to amend to PLLC status, and IDFPR has pursued the distinction. An attorney practising through a standard LLC formed before the change should confirm their position rather than assume it was handled.
Yes. Rule 7.5 permits firm names and letterheads that are not misleading, which is the governing standard rather than any requirement to use your own surname. A sole proprietor registers an Assumed Name; a PLLC establishes its name in the Articles of Organization.
The signature nobody thinks about
The moment this actually matters arrives about six weeks into a new practice, and it doesn’t feel like a legal question at the time.
Someone hands you a lease, or a copier agreement, or a staffing contract. You read the terms, you agree the terms, and you sign — and the only question in your mind is whether the terms are fair.
The question you didn’t ask is who exactly is signing.
If you’ve formed nothing, the answer is you. Not the practice, not the firm, not a business. You, personally, for the full term, whatever happens to the practice in the meantime.
It costs $200 to change that answer.
I’ve watched enough practices open and close to think that’s the cheapest thing on any startup list, and the one most likely to be skipped because it doesn’t feel urgent in week one.
It isn’t urgent. It’s just much harder to fix afterwards.
Questions about any of this? 312.924.0200 or [email protected].
Ron Bockstahler is the founder and CEO of Amata Law Office Suites, a vendor member of the Chicago Bar Association, supporting Chicago-area law firms since 2002. He co-hosts The 1958 Lawyer podcast.
Amata Law Office Suites is not a law firm and does not provide legal services to the general public. This article is general information, not legal or tax advice. Entity selection has tax and liability consequences specific to your situation — consult your own counsel and accountant. Filing fees and requirements change; verify current figures with the Illinois Secretary of State and IDFPR before relying on them.
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