Ontario postjudgment interest, explained

What postjudgment interest is

Postjudgment interest is interest that accrues on an unpaid judgment after it is entered, until it is paid. Section 129 of the Courts of Justice Act sets the default rule for Ontario courts.

When it starts and stops

Postjudgment interest runs from the date of the order to the date of payment. If the debtor pays part of the judgment, interest continues to accrue on the unpaid balance.

Which rate applies

The default rate is set by reference to the bank rate at the end of the first day of the last month of the quarter preceding the quarter in which the order was made. Ontario publishes the quarterly table online. Use the rate for the quarter the judgment was granted - not the quarter of payment or the quarter of calculation.

Simple interest, not compound

Section 127 provides for simple interest. Interest does not itself earn interest, unless a statute, agreement, or order specifically provides for compounding.

Applying payments

When a partial payment is received, apply the payment first to accrued interest and then to principal, unless the order, the parties' agreement, or applicable law directs otherwise. Reducing principal this way reduces the interest that accrues going forward.

What the interest actually runs on

Postjudgment interest runs on the judgment as entered. Where the order includes costs and prejudgment interest, those amounts form part of the sum that carries postjudgment interest - so pulling only the damages figure off the front page of the order understates the balance. Costs that are fixed later in a separate order generally carry interest from the date of that later order, not from the date of the original judgment. Read the order, and where costs were dealt with separately, treat each order as its own interest run.

Keeping a payment record you can defend

Interest is only as reliable as the payment history behind it. Keep a dated record of every amount received, from whatever source, including garnishment remittances and money paid into court. Two habits cause most disputes: crediting a payment on the day it cleared rather than the day it was received, and recording several payments as one lump sum at the end of the period. Both shift the balance that interest runs on. Where enforcement is underway, reconcile against the enforcement office's statement rather than your own ledger alone.

Verification workflow before you enforce or settle

1. Take the judgment date from the entered order, not the hearing date or the endorsement date.
2. Identify the quarter of the order and read the postjudgment rate for that quarter from the Ministry table, including its notes.
3. Confirm the base amount from the face of the order: damages, costs and any prejudgment interest included in it.
4. List every payment received, in date order, with its source, and confirm the total against your receipts.
5. Check the order and any settlement or payment agreement for interest terms or an allocation direction that displaces the default assumption.
6. Recalculate to the specific date you intend to quote - a payout figure is only valid for the day it was calculated to - and state that date whenever you give the number to another party.

When the ordinary rule can be displaced

Section 130 gives the court discretion to order a different rate or period in appropriate cases. A contract can also provide a different rate that continues past judgment where the debt merges into the judgment. Check the order itself - some judgments specify a non-default rate on the face of the order.

Next steps

With the rate, the base amount and the payment history settled, run the numbers through the Ontario Court Interest Calculator in postjudgment mode and keep the period-by-period breakdown with the enforcement file. If you also need the interest that accrued before judgment, that is a separate calculation on a different rate - see the prejudgment interest guide. Before issuing an enforcement step or accepting a payout figure, have the arithmetic and the entitlement checked by a lawyer or licensed paralegal.