Free Canadian Mortgage Tool
Mortgage Rate Difference Calculator Canada
A small mortgage rate difference can change both the monthly payment and the amount of principal repaid during the term. Enter one mortgage amount, amortization and term, then compare two rates using Canadian semi-annual compounding to see the true payment and interest difference.
Short answer
How much difference does a small change in mortgage rate make?
A fraction of a percentage point looks trivial monthly and is substantial over a full term, because it applies to a large balance for years. Comparing two rates properly means looking at the payment, the interest paid over the term, and the balance left at renewal — a lower rate builds equity faster as well as costing less. A rate advantage can also be cancelled out by a restrictive prepayment penalty calculation or a low prepayment privilege, so compare the terms alongside the number.
Compare two rates
Rate B saves over 5 years
$11,994
Monthly payment difference: $141
Rate A · 4.99%
Monthly payment
$2,905
Interest over term$116,779
Balance at renewal$442,468
Rate B · 4.49%
Monthly payment
$2,765
Interest over term$104,784
Balance at renewal$438,909
Results are estimates for general guidance only and do not constitute an offer of credit. Actual figures depend on lender policy, credit history, and verified documentation. Call (604) 780-5173 for exact numbers.
Key takeaways
- A 0.10 percentage-point difference is 10 basis points, not a 0.10% reduction in the payment.
- On a $500,000 mortgage, a 0.50-point rate gap often changes the payment by roughly $140 per month.
- Compare interest and the balance at renewal, not only the monthly payment.
- Fees, penalties and restrictions can outweigh a small rate advantage.
- Canadian fixed-rate calculations use semi-annual compounding, so US calculators produce different figures.
What a mortgage rate difference really costs
Rate differences are quoted in percentage points or basis points. Moving from 4.99% to 4.49% is a drop of 0.50 percentage points, or 50 basis points. The payment does not fall by 10%; the exact change depends on the balance and amortization.
The calculator holds the mortgage amount, amortization and term constant so the rate is the only changing variable. That isolates the cost of the rate itself.
Why term interest is more useful than payment alone
A lower rate reduces the interest portion of each payment and usually sends slightly more principal to the balance. The benefit is therefore the interest saved during the term, while the balance at renewal shows the additional equity created.
Looking only at payment understates this benefit. It can also mislead when two offers use different amortizations, which is why this focused page fixes the amortization for both rates.
When the lower rate is not the better mortgage
A restrictive low-rate product may carry a larger penalty, prohibit porting, require a bona fide sale before discharge, or charge setup fees. Add those differences before choosing an offer. The separate mortgage comparison calculator handles fees and different terms side by side.
For variable rates, rerun the calculation at several possible future rates. Today's payment difference is not a forecast of the full term because prime can change.
Using rate savings in BC, Alberta and Ontario
The mortgage formula is the same across the three provinces, but closing and switching costs can differ. Ontario and BC purchases may carry material transfer taxes, while Alberta registration costs are lower. Those purchase costs do not change merely because the lender rate changes.
At renewal, ask whether the new lender covers appraisal, legal, transfer, or discharge costs. A small rate saving can disappear if switching fees are paid personally.
Worked example
Worked example: 4.99% versus 4.49%
| Mortgage amount | $500,000 |
|---|---|
| Amortization | 25 years |
| Term | 5 years |
| Payment at 4.99% | about $2,908 monthly |
| Payment at 4.49% | about $2,768 monthly |
| Monthly difference | about $140 |
| Interest difference over term | roughly $12,000 |
The lower rate improves monthly cash flow and reduces interest. Fees and contract restrictions still need to be compared before accepting the offer.
Frequently asked questions
How much difference does 0.5% make on a mortgage?
On a $500,000 mortgage amortized over 25 years, a 0.50-point rate difference is commonly around $140 per month and roughly $12,000 of interest over five years.
How much does 0.25% save on a mortgage?
On $500,000 over 25 years, 0.25 percentage points is roughly $70 per month. The exact term saving depends on the rates and remaining amortization.
What is one basis point on a mortgage?
One basis point is 0.01 percentage points. A move from 4.50% to 4.40% is 10 basis points.
Should I choose the lowest mortgage rate?
Not automatically. Compare fees, prepayment privileges, portability, penalty wording and refinance restrictions as well as the interest saving.
Does a lower mortgage rate pay more principal?
Yes, when the mortgage amount and amortization are held constant. Less of each payment goes to interest, and the balance at renewal is generally lower.
Why is a Canadian mortgage calculator different?
Canadian fixed mortgages quote nominal rates compounded semi-annually. A calculator using simple monthly division or US conventions gives a slightly different payment.
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