How to Serve a Defence in Ontario Small Claims Court

Why Service Comes Before Filing

This catches many first-time defendants: serve every other party first, then file with the court. The court requires an Affidavit of Service (Form 8A) for each party served.

The sequence under the Small Claims Court Rules (O. Reg. 258/98):

1. Complete Form 9A
2. Serve a copy on every other party (or their representative)
3. Complete Form 8A for each party served, documenting how and when you served them
4. File Form 9A + the Form 8A affidavits + $77 fee with the court clerk

All of this must happen within 20 calendar days of being served with the Plaintiff's Claim.

Acceptable Service Methods

Rule 8 sets out how court documents can be served. For a Defence, these methods all work:

Personal service. Hand a copy directly to the party. If the party is a corporation, serve an officer, director, or agent, or a person at any place of business who appears to be in control or management.

Mail. Send by regular or registered mail to the last address of the party or their representative known to you. Service is deemed effective on the fifth day after mailing.

Courier. Send by commercial courier to the last address of the party or their representative that is on file with the court or known to you. Service is deemed effective on the fifth day after the courier verifies delivery.

Leaving with a household member. If personal service cannot be effected on an individual party, leave a copy in a sealed envelope addressed to them at their residence with someone who appears to be an adult member of the same household. On the same or following day, mail or courier another copy to the party at that residence. Service is effective on the fifth day after mailing or verified courier delivery.

Email. Rule 8 permits email service of a Defence using the party's or representative's last email address provided, or, if none was provided, the last known email address. For a lawyer or paralegal whose address was not provided, use the address listed in the Law Society of Ontario directory. Service is normally effective when sent; if sent between 4 p.m. and midnight or on a Saturday, Sunday, or holiday, it is effective on the next day that is not a Saturday, Sunday, or holiday.

Proof of Service: Form 8A

Form 8A (Affidavit of Service) is a sworn document confirming who you served, when, where, and by what method. It must be commissioned — sworn or affirmed before a commissioner for taking affidavits.

Where to get Form 8A commissioned:

• Many licensed paralegals and lawyers will commission affidavits for free or a small fee
• Some courthouse service counters offer commissioning
• Remote commissioning via video call is legally valid under O. Reg. 431/20 if the commissioner verifies your identity, sees and hears you in real time, confirms the signed document matches the document presented, and completes a jurat stating that it was commissioned remotely under the regulation

The jurat (the sworn statement at the bottom of Form 8A) must explicitly state the commissioning method. If done remotely, it must reference O. Reg. 431/20.

Timing Traps

Registered mail adds days. If you mail Form 9A by registered mail on day 12 of your 20-day window, service is deemed effective on day 17 (five days later). You then need to file with the court by day 20. That's tight — leave more margin than you think.

Use the correct email address and timing. Follow Rule 8.08 for the email address and deemed service date, especially if the email is sent after 4 p.m.

Serving the wrong person. If a party is a corporation, serving a receptionist or random employee does not count by itself. Serve an officer, director, or agent, or someone who appears to be in control or management at a place of business.

If You Can't Locate the Plaintiff

Occasionally the plaintiff's address on Form 7A is wrong or they can't be found. In that case, you can bring a motion under Rule 8.04 for an order allowing substituted service — serving by regular mail, posting, or even social media. This requires a Form 15A motion ($127 fee) and evidence that you've tried the standard methods.

For defendants, this is rare — the plaintiff initiated the case, so their contact information is usually on their own Form 7A.

What Happens After Service

Once your Form 8A affidavits are commissioned and filed alongside Form 9A, the court processes your Defence. Assuming no deficiencies, the clerk accepts it into the record and schedules a settlement conference unless the Defence admits the full claim and proposes terms of payment. You'll receive a Notice of Settlement Conference if a conference is scheduled.

Our Ontario Small Claims Court Defence Guide walks through every service method with deadline calculators, a Form 8A completion checklist, and the exact commissioning requirements.

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