Mortgage calculator

Mortgage prepayment penalty calculator

Estimate three months' interest and a simplified interest-rate-differential amount before requesting a lender payout quote.

Reviewed August 31, 2026Published by Ontario Mortgage HelpCalculation standard
Illustrative penalty estimate$10,000The higher of three months’ interest and a simplified interest-rate differential.
Three months’ interest
$6,563
Simplified IRD
$10,000
Difference between rates
1.00%

This is not a lender payout amount. Contracts differ on posted rates, rate discounts, prepayment privileges, calculation dates, fixed versus variable rates, and fees. Request a written payout statement before making a decision.

How to use this estimate

Use current documents.Enter figures from the mortgage statement, renewal offer, payout quote, appraisal, or commitment where possible.

Compare like with like.Use the same balance, time period, and payment frequency when comparing alternatives.

Check the actual terms.Qualification, fees, compounding, privileges, and lender calculations may produce different results.

FCAC guidance on prepayment penalties
All calculators