Naming Rules for a Professional Corporation in Ontario: What You Can and Cannot Call It

An ordinary Ontario business corporation can pick almost any available name — an invented brand, a numbered company, whatever fits the business. A professional corporation, used by a licensed professional such as a lawyer, doctor, dentist, or accountant to incorporate their practice, doesn’t get quite that much freedom. Because the corporation exists to carry on a regulated profession, both the corporate registry and the professional’s own governing regulatory body have a say in what it can be called.

Because naming requirements genuinely differ from one regulated profession to the next, this article covers the general pattern rather than any one profession’s exact rule book — always confirm the current requirements with your specific regulator before you settle on a name.

Why Professional Corporations Follow Different Rules

A professional corporation exists specifically so a licensed member of a regulated profession can carry on that profession through a corporate structure, rather than as a sole proprietor. Because the corporation is standing in for a licensed individual’s practice, the professional’s regulatory body — often called a "College" — typically has to approve the corporation, including its name, before it can practise. That’s an extra layer of scrutiny an ordinary business corporation never encounters.

The General Pattern Across Regulated Professions

While the specifics vary, most Ontario professional corporation naming regimes share a similar shape:

• The name typically must include the surname of one or more individuals authorized to practise the profession who are (or, in some cases, were) shareholders of the corporation. A professional corporation generally can’t operate under a purely invented brand name the way an ordinary business can.
• A required designation. The legal name generally needs to identify the entity as a professional corporation — for example, including "Professional Corporation" or an approved abbreviation.
• No suggestion of unrelated business activity. Names generally can’t include wording that implies the corporation carries on any business beyond the regulated profession it’s authorized for, or that could mislead the public about who owns or controls it.
• A second approval layer. Beyond the standard corporate name-search process, the professional’s own regulatory body typically needs to approve the corporation and issue its own authorization before the corporation can actually practise under that name.

This Varies by Profession — Confirm With Your Regulator

The exact naming requirements, permitted abbreviations, and approval process differ from one regulated profession to another — law, medicine, dentistry, accounting, engineering, and other professions each have their own governing body with its own rules, and those rules can change. Before you settle on a name, confirm the current requirements directly with your profession’s regulatory body and with a lawyer experienced in that profession’s incorporation process.

Practical Naming Checklist

• [ ] Confirm whose surname(s) may — or must — appear in the corporation’s name
• [ ] Confirm the exact designation both your regulator and the corporate registry require
• [ ] Avoid any wording suggesting a business activity outside your regulated profession
• [ ] Clear the proposed name through the standard corporate name-search process
• [ ] Obtain your regulator’s approval or certificate of authorization before assuming the corporation is fully authorized to practise
• [ ] Plan ahead for what happens to the name if a named shareholder later leaves the corporation, since many regimes require the name to reflect current or former professional shareholders in a specific way

Two Separate Approvals, Not One

It’s worth being clear-eyed about this: the corporate registry and your professional regulator each apply their own rules, independently. A name that clears the corporate registry’s database check isn’t automatically approved by your regulator, and vice versa. Practising or holding your business out under a name your regulator hasn’t approved can be a professional-conduct issue even if the corporate registry accepted the name — the two processes don’t guarantee each other.

Frequently asked questions