How is it calculated?
Variable mortgages usually charge three months' interest. Fixed mortgages charge the greater of three months' interest and the interest rate differential (IRD).
$400,000 at 4.89%, 24 months left, lender rate 3.99%
IRD = 0.90% × $400,000 × 2 = $7,200
What should I do with the result?
Use it to set a budget or a target rate, then let brokers and lenders bid on your actual mortgage. Bids include rate, penalty method, prepayment and fees, so you can compare the full cost.
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Licensed mortgage brokers bid alongside banks, credit unions and private lenders on MortgageBids.ca. One broker bid can tap dozens of lenders, and on most prime mortgages the lender pays the broker, not you. Why use a mortgage broker · Get broker and lender bids
MBWritten by the MortgageBids.ca editorial team. Last updated October 7, 2026. General information only; your lender confirms terms for your file.
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