Who Can You Sue in Ontario Small Claims Court?

It's a strange feature of Small Claims Court that a case can be entirely justified on the facts and still run into trouble — not because of what happened, but because of who was named to answer for it. Figuring out the correct defendant is a legal question in its own right, separate from whether you have a good case, and it deserves real attention before you file anything.

Why naming the right defendant matters so much

A judgment is only as useful as your ability to enforce it against the party actually named on it. If you sue an individual personally for a debt that legally belonged to their corporation, or sue a corporation for something an individual did in a purely personal capacity, you can end up with a technically valid judgment against a party that has no connection to the money or assets you're actually trying to reach. Getting this right at the outset isn't a formality — it's often the difference between collecting on a judgment and holding a piece of paper you can't enforce.

It also matters earlier than that. Naming the wrong defendant can slow a case down long before judgment, since a defendant who genuinely isn't the correct party may respond by disputing that they're properly before the court at all — a procedural argument that can consume time and attention that would otherwise go toward the actual merits of your dispute. Spending an extra half hour confirming a name properly at the outset is almost always cheaper than untangling the consequences later.

For the official government description of how a claim identifies the parties involved, see the guide to procedures in Small Claims Court on making a claim.

Suing an individual

The simplest case: one person owes you money, damaged your property, or failed to deliver something they personally agreed to provide. Here, you generally name that person directly, using their full legal name rather than a nickname. If you only know someone by a first name or a username, it's worth doing some legwork — checking a lease, an invoice, a text message signature, or a social media profile — to confirm a full legal name before filing.

A tricky variation: someone who did work for you personally but describes themselves using a business-sounding name on their invoices. This is usually still an individual operating a sole proprietorship, which brings in the next category.

Suing a sole proprietorship

A sole proprietorship isn't a separate legal entity — legally, the business and its owner are the same person. If you hired "Smith Contracting" and it turns out Smith Contracting is just Jane Smith operating under a business name, your claim is generally against Jane Smith personally, sometimes described on the claim as "Jane Smith, carrying on business as Smith Contracting." This matters because it confirms whose personal assets and income could eventually be reached to satisfy a judgment.

A business name registration, where one exists, can help confirm the legal individual behind a trade name — it's worth checking before you assume a business is something more formal than a sole proprietorship.

Suing a partnership

Depending on how a partnership is structured, a claim may be brought against the partnership itself, against the individual partners, or both. Because the details can turn on the specific partnership arrangement — which isn't always visible to an outside customer or client — this is a scenario worth pausing on rather than guessing. If you're dealing with what appears to be a partnership and the amount at stake is significant, a quick professional opinion on how to structure the claim can be worthwhile.

Suing a corporation

A corporation is a separate legal entity from the people who own or run it — a fact that surprises people more often than you'd expect. If you did business with "Smith Contracting Inc.," the corporation is generally the correct defendant for a dispute over the corporation's money or obligations, not Jane Smith personally, even if Jane Smith is the sole owner and the person you dealt with the entire time.

There are situations where an individual behind a corporation can be personally liable too — for example, in some cases involving personal guarantees or certain kinds of misconduct — but that's a narrower, fact-specific question, not the general rule. Don't assume you can simply add an owner's name to a corporate claim "to be safe" without a genuine legal basis for doing so.

Individual vs. sole proprietorship vs. corporation as a defendant

Naming more than one defendant

You can generally name more than one defendant on a single claim where they're connected to the same dispute — for example, a contractor and a subcontractor who both played a role in defective work, or two individuals who jointly agreed to repay a loan. Each defendant still needs to be properly identified and served individually, and each should have a genuine connection to the dispute rather than being added on the chance that one of them turns out to have money.

Defendants that are harder to pin down

Some situations are genuinely more complicated, and it helps to recognize them early rather than being caught off guard partway through preparing a claim.

• A business that has closed or restructured. Don't automatically assume there's no one left to sue — a successor company, or the individuals behind a dissolved business, may still be identifiable defendants depending on exactly what happened.
• A defendant who has moved or is hard to locate. This affects service more than naming, but it's worth researching a current address — through former addresses, workplaces, or public records — before you file.
• A defendant outside Ontario. Different procedural rules can apply, so confirm the requirements rather than assuming your usual approach applies unchanged.
• A government body or public institution. Claims against government entities can involve additional notice requirements — this is worth confirming specifically.

Using a demand letter to test the name before you file

One practical way to confirm you have the right defendant before spending a filing fee is to send a demand letter first, addressed to the name you believe is correct. How the recipient responds — correcting the name, confirming it, or simply staying silent — can itself be useful information. A demand letter is also, on its own terms, a low-cost way to possibly resolve the dispute entirely before a claim is ever needed, which is worth keeping in mind alongside its usefulness for confirming who you're actually dealing with.

Confirming you have the right defendant

A few practical steps go a long way toward confirming you've identified the right defendant before you file: review every invoice, contract, receipt, and piece of written communication for the exact name used; check whether a business name is registered and to whom; check a corporate name search if a business could be incorporated; and, if there's genuinely any doubt, consider a brief consultation with a lawyer or licensed paralegal before committing to a name on your claim. The Ontario Superior Court of Justice's guide to the Small Claims Court process is a useful starting point for understanding how the court expects parties to be identified.

For the shorter, task-focused version of this same question, see our guide on who can sue in Small Claims Court, which also covers who has standing to bring a claim as a plaintiff.

Common mistakes

• Suing an individual for a corporation's debt, or vice versa.
• Using only a trade name instead of the underlying legal person or entity.
• Adding an owner's name to a corporate claim without a genuine legal basis for personal liability.
• Assuming a closed business means there's no one left to sue, without confirming what actually happened to it.
• Guessing at a spelling or name instead of confirming it against a document or registry.

What to do next

1. Gather every document that names the party you dealt with — invoices, contracts, emails, texts (a claim preparation checklist can help).
2. Determine the legal structure — individual, sole proprietorship, partnership, or corporation.
3. Confirm the exact legal name through a registration or corporate search if there's any doubt.
4. Decide whether more than one defendant genuinely belongs on the claim.
5. Write the defendant's name on your claim exactly as confirmed, not from memory.

Frequently asked questions

This article is general legal information, not legal advice about your specific situation. See our disclaimer for more detail, and consider speaking with a lawyer or licensed paralegal if you're genuinely unsure who to name as a defendant.