- Ontario's Courts of Justice Act sets out two distinct types of interest that generally apply to civil judgments, including those from Small Claims Court: 1.
- Prejudgment interest generally runs from the point your claim arose (or a related date tied to when you were entitled to the money) up to the date of judgment.
- Once a judge signs the judgment, a second interest clock starts.
You sued, you won, and the judgment names a dollar amount. But the number on the judgment isn't always the full number you're entitled to collect. Ontario's civil litigation rules generally add interest on top — both for the time your claim sat unresolved and for the time it takes the debtor to actually pay after judgment.
Understanding small claims judgment interest matters because it can meaningfully change what you're owed, especially if a case took a long time to resolve or the debtor is slow to pay.
The Short Answer: Interest Applies in Two Separate Ways
Ontario's Courts of Justice Act sets out two distinct types of interest that generally apply to civil judgments, including those from Small Claims Court:
- Prejudgment interest — compensation for the period before judgment, while your money sat unpaid.
- Postjudgment interest — compensation for the period after judgment, until the debtor actually pays in full.
Both exist for the same basic reason: money owed to you today is worth more than the same amount paid years from now, and interest is meant to account for that gap.
Prejudgment Interest: For the Wait Before Judgment
Prejudgment interest generally runs from the point your claim arose (or a related date tied to when you were entitled to the money) up to the date of judgment. The rate is not fixed permanently — it's set periodically by the province and applied to civil judgments across Ontario, including Small Claims Court awards.
As an illustration only: the prejudgment interest rate sat at 2.5% in Q3 2026. That figure is reset quarterly, so it will not be accurate indefinitely — always confirm the current rate before calculating what you're owed.
Postjudgment Interest: For the Wait After Judgment
Once a judge signs the judgment, a second interest clock starts. Postjudgment interest accrues on the unpaid balance from the date of judgment until the debtor pays in full — which matters a great deal if enforcement takes time.
As of Q3 2026, the postjudgment rate sat at 4.0%, again reset quarterly. If a debtor delays payment for a long stretch after judgment, this interest can add up to a meaningful amount on top of the original award.
Why the Rate Keeps Changing
Both rates are tied to the Courts of Justice Act and are adjusted on a regular schedule rather than fixed by the statute itself. That's a deliberate design — a rate set once and never revisited would quickly become disconnected from real borrowing costs. It also means you should never assume a rate you saw quoted somewhere online, or even in an older article, still applies to your case today.
Is Interest Automatic, or Do You Have to Ask For It?
Generally, prejudgment and postjudgment interest are considered as part of a judgment without you needing a separate lawsuit to claim them — but it's still worth explicitly asking for interest when you file your claim, so the judge has the request in front of them. One important wrinkle: if your contract, invoice, or agreement with the other party already sets its own interest rate for late payment, that agreed rate generally takes priority over the court's default calculation instead of stacking on top of it.
Calculating What You're Actually Owed
| Period | What Applies |
|---|---|
| Before your claim was filed / during the lawsuit | Prejudgment interest on the amount owed |
| From judgment until paid in full | Postjudgment interest on the unpaid balance |
| Throughout, if your contract sets its own rate | The contractual rate may apply instead of the statutory default |
In practice, the calculation is straightforward once you know the applicable rate for each period, but it does require pulling the correct rate for the correct stretch of time — not just applying today's rate retroactively to the whole claim.
Frequently asked questions
Do I need to specifically ask the court for interest, or is it added automatically?
It's best practice to request interest explicitly in your claim. While courts generally apply it as a matter of course, putting it in writing avoids any ambiguity about whether you're seeking it.
Can I just use my own invoice's interest rate instead of the court's rate?
If your invoice, contract, or agreement already specifies an interest rate for late payment, that rate can generally apply instead of the statutory default — but this depends on the wording of your agreement, so it's worth having a lawyer confirm it applies as you expect.
Does interest keep accruing even after I get the judgment but before I actually collect?
Yes. Postjudgment interest continues to accrue on the unpaid balance until the debtor pays in full, which is one more reason not to delay enforcement once you have a judgment in hand.
Is interest calculated on the amount I originally claimed or the amount the judge actually awarded?
Interest is calculated on the amount the judge actually awarded — not your original claim, which may have been higher.
This is a litigation question
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