How to File a Defence in Small Claims Court in Ontario

A Small Claims Court claim has arrived with your name on it. Someone says you owe them money, or that you damaged something of theirs, and the envelope came with a court seal. It is a stressful moment, and the most useful thing to know first is that a clock is now running.

In Ontario, a defendant who wants to dispute a Small Claims claim has 20 days to serve and file a defence. This guide explains what that deadline means, what a defence has to contain, how it is served and filed, and what happens if nothing is filed. It is general information about the process, not advice about any particular case.

A few terms first

Plaintiff: the person or business that started the case by suing.
Defendant: the person or business being sued.
Claim: the court document that starts the case. In Small Claims Court it is the Plaintiff's Claim, and it sets out what the plaintiff says is owed and why.
Defence: the defendant's written answer to the claim. It uses a court form called the Defence (Form 9A).
Served: formally given a court document in a way the rules allow.
Monetary limit: the largest amount a Small Claims case can be for. The province's page on suing someone in Small Claims Court says the limit increased from $35,000 to $50,000 effective October 1, 2025.

Key date: the 20-day deadline to file a defence

Rule 9.01 of the Rules of the Small Claims Court, O. Reg. 258/98 says a defendant who wishes to dispute a plaintiff's claim shall, within 20 days of being served with the claim:

serve a defence (Form 9A) on every other party, and
file the defence, with proof of service, with the court clerk.

The province's guide to replying to a claim describes this as 20 calendar days from the date you were served. A few points about how those days are counted, all from the same rules:

Counting: under rule 3.01, the first day is excluded and the last day is included. If the last day falls on a holiday, the period ends on the next day that is not a holiday. The rules define "holiday" to include every Saturday and Sunday.
Claim left at a home or sent to a corporation: rule 8.01(1) requires a claim to be served personally or by an alternative to personal service under rule 8.03. Under rule 8.03(4), service by leaving a copy with an adult at the home and also mailing or couriering a copy, or by mailing or couriering a copy to a corporation, is effective on the fifth day after the copy is mailed or the courier verifies that it was delivered.
Registered mail or courier with a signature: under rules 8.03(7) and (8), a claim sent to an individual's home this way is served on the date receipt is verified by signature.

Write down the date and method of service as soon as the claim arrives. If you are unsure when your 20 days began, treat that as a reason to act early.

Your choices when you are served

A defence is not only for people who disagree with everything in a claim. The Defence form and the rules allow for several positions:

Dispute the whole claim and explain why.
Admit part of the claim and dispute the rest.
Admit all or part of the claim and propose terms of payment. Rule 9.03 lets a defendant who admits liability, but wants to arrange payment, propose terms in the defence. The province's guide gives weekly or monthly payments as examples. Under rule 9.03(3), the plaintiff then has 20 days after service of the defence to dispute that proposal and ask for a terms of payment hearing.

Separately, a defendant may have a claim of their own. Rule 10.01 allows a defendant's claim (Form 10A) against the plaintiff, or against another person where it arises from the same events or relates to the plaintiff's claim. It may be issued within 20 days after the defence is filed, or later with the court's permission, before trial or default judgment.

What a defence must contain

Rule 9.02 sets out the requirements. A defence must contain:

the reasons the defendant disputes the plaintiff's claim, "expressed in concise non-technical language with a reasonable amount of detail";
if the defendant is self-represented, the defendant's name, address, telephone number and email address (if any); and
if the defendant has a representative, the representative's name, address, telephone number, email address (if any) and Law Society of Ontario registration number (if any).

If the defence is based in whole or in part on a document, such as a contract, invoice, receipt or letter, a copy must be attached to each copy of the defence. If the document is unavailable, the defence must say why it is not attached.

How to write a defence for Small Claims Court

The rule's own wording is a useful guide. Plain language is expected, not legal phrasing, with enough detail for the plaintiff and the court to understand your position. In general terms, a clear defence:

responds to what the claim actually says, point by point where that helps;
states plainly what you agree with, what you dispute and why;
sets out relevant dates, amounts and events in order; and
attaches the documents it relies on.

What belongs in your own defence depends on the facts of your case, which is where individual advice can help.

How to file a defence: the steps

The province's guide to replying to a claim and the rules set out this sequence:

Complete the Defence (Form 9A). Include your reasons, contact information and any attached documents, as described above.
Serve a copy on every other party. Under rule 8.01(14), a defence may be served by mail, by courier, by email, personally, or by an alternative to personal service allowed by the rules, unless the court orders otherwise.
Prove service. Under rule 8.09.1, service may be proved by an affidavit of service (Form 8A) of the person who served it. A lawyer or paralegal may instead use a certificate of service (Form 8B). The guide says to complete one affidavit of service for each party served.
File the defence with the court, with proof of service and the filing fee, within the 20 days. The guide directs readers to the court's fee information for current amounts.

Can you file a defence online?

Yes, in most cases. The province's guide lists three ways to file a defence:

Online, through the Small Claims Court Submissions Online portal;
In person at the courthouse; or
By mail, sending the defence, supporting documents and affidavit(s) of service, together with the fee, to the Small Claims Court.

Toronto is different. The province's page on filing Small Claims Court documents online says that starting October 14, 2025, all online filings for the Toronto region must be submitted using the Ontario Courts Public Portal. That page lists what you need to file online:

an Ontario.ca login;
a Visa, Mastercard or debit card, if filing fees apply; and
your court file number, if you are filing for an existing case.

You also need an email address. Rules 1.05.4(2)(b) and 1.05.5(3)(b) require the person filing through either portal to give an email address at which they agree to accept documents from the court.

Under rules 1.05.4 and 1.05.5, a document submitted through either portal counts as filed only once the clerk confirms it, on the date shown in that confirmation. The same online filing page says the portal cannot be used to meet a deadline that is 3 business days or less away. In that case it points to filing in person, by mail or by email instead.

What "noted in default" means if no defence is filed

If a defendant does not file a defence within the prescribed time, rule 11.01 allows the clerk to note the defendant in default when the plaintiff files a request and proof of service. The province's suing page explains the effect plainly: when the defendant is noted in default, the court can assume the defendant admits they owe the money.

The rules then set out what follows:

Default judgment for a fixed amount. Under rule 11.02, where the claim is for a debt or other fixed sum of money, the clerk may sign default judgment (Form 11B), including interest if claimed.
Other amounts. Under rule 11.03, for parts of a claim that are not a fixed sum, the plaintiff may ask for an assessment in writing or at a hearing. The plaintiff is not required to prove liability against a defendant noted in default, but is required to prove the amount.
Limits on the defendant. Under rule 11.05, a defendant noted in default may not file a defence or take any other step, except a motion to set aside, without the court's permission or the plaintiff's consent. That defendant is also not entitled to notice of most further steps.

Noting in default is not always the end of the matter. Under rule 11.06, the court may set aside a noting in default or a default judgment, on terms that are just, if the party brings a motion and the court is satisfied that the party has a meritorious defence and a reasonable explanation for the default, and that the motion was made as soon as reasonably possible. The province's guide also describes setting aside a default with the consent of all parties. Whether either route is available depends on the circumstances, and the court decides.

What happens after a defence is filed

Under rule 13.01, a settlement conference is held in every defended action, within 90 days after the first defence is filed. The clerk fixes the time, date and place. The province's suing page describes it as a meeting where both sides share their evidence and try to resolve the dispute. An exception applies where the defence admits the whole claim and proposes terms of payment.

Representing yourself or having a representative

The province says you do not need to hire a lawyer or paralegal for a Small Claims case. The rules define a "representative" as the lawyer, paralegal or other person representing a person in a proceeding. Our earlier guide on who can represent you in Small Claims Court explains those choices for both plaintiffs and defendants.

AI Paralegal Services is a licensed paralegal practice led by Lisa Duchene. Small Claims claims and defences are among the services we provide across Ontario.

In summary

A Small Claims defence is a short, plain-language form with a firm deadline: 20 days from service to serve it on every other party and file it, with proof of service. It can dispute the claim, admit part of it or propose terms of payment, and it can be filed online, in person or by mail. If nothing is filed, the defendant can be noted in default and judgment can follow.

If you have been served with a Small Claims claim and want to understand your options before the deadline, AI Paralegal Services can review the details with you. Contact us to arrange a consultation or send your matter details through intake.

This article is general information about Ontario Small Claims Court procedure as of October 2026. It is not legal advice about your situation, and reading it does not create a paralegal-client relationship. Rules and procedures change, so check the current official sources, and speak with a licensed legal professional about your own matter.