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Home/Secretary of State directory/Professional LLC and PC/Illinois Professional LLC + Professional Corporation
Illinois . Professional Entity

Illinois Professional LLC + Professional Corporation.

Licensed professionals in Illinois . doctors, lawyers, accountants, architects, engineers, and others . often must form a Professional LLC (PLLC) or Professional Corporation (PC) rather than a standard entity. This guide explains who qualifies, the licensure requirements, and what differs in formation.

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Who must form a professional entity in Illinois

Illinois typically requires a Professional LLC or Professional Corporation for state-licensed services including:

  • Medical: physicians, surgeons, dentists, psychologists, chiropractors, optometrists.
  • Legal: attorneys and law firms.
  • Accounting: CPAs.
  • Engineering + Architecture: licensed PEs and architects.
  • Real estate: brokers in some Illinois jurisdictions.
  • Other professionals licensed under Illinois occupational codes.
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Guide

Professional LLC and PC by state

The national explainer above this page: what changes between jurisdictions, and why.

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Secretary of State directory

Every filing the state business office takes, state by state.

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Illinois business filings

Every filing a business makes in Illinois, gathered on one page.

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Entity conversion in Illinois

Entity conversion, state by state

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Registered agent in Illinois

Registered agent rules, state by state

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Secretary of State in Illinois

The Secretary of State, state by state

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Secretary of State annual report in Illinois

The annual report, state by state

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Licensed professions

Illinois Professional Service Entity: at a glance.

PLLC or professional corporation filing for licensed professions (medical, legal, accounting, etc.).

Filing details

How Illinois handles Professional Service Entity.

Illinois Business SearchLook up any Illinois entity and read every status right.
Where to fileSecretary of State office, online portal, or by mail with the required fee.
TurnaroundStandard processing: 5-10 business days. Expedited service available for an additional state fee.
Required informationEntity name + ID, current officers and registered agent, principal office address.
Common pitfallsMismatched officer addresses, expired registered agent, missed prior reports causing administrative dissolution.
Frequently asked

Illinois Professional Service Entity questions.

What is a professional service entity in Illinois?

It is a special entity, a PLLC or professional corporation, that Illinois requires or offers for licensed professionals, doctors, lawyers, accountants, engineers, to deliver their services, with ownership generally limited to licensed people. A regular LLC often will not be accepted for licensed work, so we confirm the Illinois entity your profession requires before filing.

Who needs to form a professional entity in Illinois?

Typically state-licensed professionals whose boards require it, though which professions and whether it is mandatory vary by Illinois. Some states route all licensed professionals into a PLLC or PC; others make it optional. We check Illinois's rule for your specific license so you form the entity the board will accept.

What is the difference between a PLLC and a PC?

A PLLC is a professional LLC, pass-through and simpler, while a professional corporation follows corporate formalities and can elect S-corp or C-corp tax treatment; both restrict ownership to licensed professionals. Illinois may prefer or require one. We help you choose the Illinois professional entity that fits your practice and tax goals.

Does the Illinois board have to approve the entity?

Often yes: many Illinois licensing boards must certify or approve a professional entity's formation, an extra step a regular LLC skips, and skipping it can delay or void the filing. We coordinate the Illinois Secretary of State filing with the board approval so both are handled in the right order rather than one blocking the other.

How is a professional entity taxed in Illinois?

Like its base type: a PLLC is pass-through by default and can elect S-corp; a PC is taxed as a corporation unless it elects otherwise. The professional designation affects licensing and ownership, not the tax classification. We help you pick the Illinois tax treatment that fits a profitable practice.

Can I convert my regular Illinois LLC to a professional entity?

Often yes where Illinois allows, by amending to meet the professional requirements, confirming licensed ownership, and getting board approval. If you have been practicing through a standard LLC, correcting the structure matters. We handle the Illinois conversion so the entity and license align properly.

Can File.Business form an Illinois professional entity?

Yes. We confirm the Illinois requirement, prepare the PLLC or PC filing, coordinate any licensing-board approval, and set up the ownership and tax election, so your licensed practice operates through the entity Illinois actually requires rather than a standard LLC the board may reject.

Related

Related services

Illinois Secretary of StateOverview, contact, full filing index. Annual reportDue dates, fees, and how to file. Registered agentRequirements and renewal. Compliance calendarEvery deadline that touches your entity.

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