How to File a Statement of Defence in Ontario (2026 Guide)

If you have been served with a Statement of Claim in Ontario Superior Court, the clock is ticking. You have a strict deadline to file your Statement of Defence — and if you miss it, the plaintiff can obtain a default judgment against you, potentially without you ever getting to tell your side of the story.

This guide explains how to respond to a Statement of Claim by preparing and filing a Statement of Defence in Ontario.

Important disclaimer: This article is for general informational purposes only and does not constitute legal advice. Ontario court rules are complex, and failing to file a defence on time can have serious consequences. For advice specific to your situation, consult a licensed lawyer or paralegal.

What Is a Statement of Defence?

A Statement of Defence is the defendant's formal response to a Statement of Claim. It is governed by Rule 18 of the Rules of Civil Procedure, R.R.O. 1990, Reg. 194, and the prescribed form is Form 18A.

The Statement of Defence tells the court:

Which facts in the Statement of Claim you admit (agree are true)
Which facts you deny (dispute)
Which facts you say you have no knowledge of
Any additional facts or legal defences you rely on
Whether you are making any counterclaim against the plaintiff

The Deadline: 20 Days (or 40 Days)

This is the most critical rule. After being served with a Statement of Claim, you must deliver your Statement of Defence within:

| Situation | Deadline | |----------|---------| | Served in Ontario | 20 days from date of service | | Served elsewhere in Canada or the United States | 40 days | | Served outside Canada and the United States | 60 days |

These deadlines are strict. If you do not file within the required time, the plaintiff may:

Note you in default (Rule 19.01)
Move for default judgment against you (Rule 19.04)

A default judgment can result in the court awarding the plaintiff everything they asked for — damages, interest, costs — without your input.

What Happens If You Miss the Deadline?

If you are noted in default, you lose the right to participate in the proceeding unless you successfully bring a motion to set aside the default (Rule 19.03). To succeed, you generally must show:

A reasonable explanation for the delay
A meritorious defence — that you have a real defence to the claim
That setting aside the default would not cause undue prejudice to the plaintiff

It is far better to file your defence on time than to litigate a motion to set aside default.

How to Draft a Statement of Defence (Form 18A)

Step 1: Address Each Paragraph of the Claim

Go through the Statement of Claim paragraph by paragraph and respond to each allegation:

Admit — if the fact is true, say so. Admitting undisputed facts focuses the trial on what actually matters. Example: "The defendant admits the allegations in paragraphs 1 through 4 of the Statement of Claim."
Deny — if the fact is false or inaccurate, deny it and (where possible) state what you say actually happened. Example: "The defendant denies the allegations in paragraph 7 of the Statement of Claim. The defendant states that the work was completed in full on June 15, 2025."
No knowledge — if you genuinely do not know whether a fact is true, say so. Example: "The defendant has no knowledge of the allegations in paragraph 9 and puts the plaintiff to the strict proof thereof."

Important: Any fact in the Statement of Claim that you do not specifically deny or say you have no knowledge of may be deemed admitted by the court (Rule 25.07(4)).

Step 2: State Your Version of the Facts

After responding to the plaintiff's allegations, set out any additional facts that support your defence. Present them in numbered paragraphs, in chronological order.

Step 3: State Your Legal Defences

Identify the legal defences you are relying on. Common defences include:

No breach — you did not breach the contract or duty alleged
Limitation period — the plaintiff's claim was filed too late (see our guide to limitation periods across Canada)
Contributory negligence — the plaintiff's own actions contributed to their loss
Failure to mitigate — the plaintiff did not take reasonable steps to reduce their damages
Set-off — the plaintiff owes you money that should be deducted from any award
Release or waiver — the plaintiff already agreed to release the claim

Step 4: State the Relief You Seek

Typically, a defendant seeks:

Dismissal of the plaintiff's claim
Costs of the action

Counterclaims, Crossclaims, and Third-Party Claims

Counterclaim (Rule 27)

If you have a claim against the plaintiff arising from the same or related facts, you can include a counterclaim with your Statement of Defence. This is a separate claim in which you become the "plaintiff by counterclaim" and the original plaintiff becomes the "defendant by counterclaim."

A counterclaim uses Form 27A (Statement of Defence and Counterclaim) or Form 27B (counterclaim only, if filed separately).

Crossclaim (Rule 28)

If there are multiple defendants and one defendant has a claim against another defendant, that is a crossclaim.

Third-Party Claim (Rule 29)

If someone not currently in the lawsuit is wholly or partly responsible for the plaintiff's claim, you can file a third-party claim to bring them into the proceeding.

Filing and Service

Filing

File your Statement of Defence at the same Superior Court of Justice office where the Statement of Claim was filed (the court file number on the claim tells you which courthouse).

The filing fee for a Statement of Defence in Ontario Superior Court is typically $144 as of 2026. Verify the current fee with the court office.

Service

Serve a copy of your Statement of Defence on the plaintiff (or their lawyer, if they have one) by regular service — mail, fax, email, or document exchange (Rule 16.05). You do not need to personally serve a defence.

Common Mistakes

Missing the 20-day deadline — this is the single most damaging mistake. Mark the deadline on your calendar immediately upon being served.
Bare denials — simply saying "denied" to every paragraph without providing your version of events is weak and may be struck by the court.
Failing to plead an affirmative defence — defences like limitation period or contributory negligence must be specifically pleaded. If you do not raise them in your Statement of Defence, you may not be allowed to rely on them later.
Ignoring the claim — some defendants assume the lawsuit will go away. It will not. Ignoring a claim leads to default judgment.
Responding emotionally — the Statement of Defence is a legal document. Keep it factual and professional.

How ProSe Can Help

Preparing a Statement of Defence under time pressure is stressful, especially if you have never done it before. ProSe helps self-represented defendants prepare properly formatted Statements of Defence through a plain-language questionnaire.

Start for free at BeProSe.ca — your first document costs nothing.

Key Resources

Ontario Rules of Civil Procedure — Rules 18, 19, 25, 27 — e-Laws Ontario (ontario.ca/laws)
Superior Court of Justice — Forms — Form 18A — ontariocourts.ca/scj/forms
Steps to Justice — Responding to a Lawsuit — stepstojustice.ca

Last reviewed: April 2026. Rules of Civil Procedure references are to the consolidated regulation as of April 2026. Court fees are subject to change; verify current fees with the court office before filing.

This article is for general informational purposes only and does not constitute legal advice. For advice specific to your situation, consult a licensed lawyer or paralegal.