Blend and extend mortgage calculator
When rates have fallen since you signed, there are three broad paths: wait for renewal, break and take today’s rate, or ask your lender to blend your current rate with a new one. This compares all three over the same period, so the numbers line up. Nothing you enter leaves your browser, and there is no sign-up.
Your mortgage today
For the break path’s penalty, using a posted rate of 5.77% for the 24 months you have left, less a discount of 1.44 points estimated from your rate, assuming a five-year term. Posted rates are the big-bank average published by the Bank of Canada, 2026-09-23; your own bank’s may differ.
The new term
Estimate · cost over the next 5 years
Break and take today's rate shows the lowest estimated cost, by about $2,966
Over 5 years, the scenario suggests breaking now costs about $2,966 less than blending and extending and $3,896 less than waiting until renewal, counting interest and any penalty. The wait path depends on the rate at renewal in 24 months, which nobody knows; it assumes 3.90%. At a renewal rate of about 3.82%, waiting and blending would cost roughly the same; above that, waiting costs more in this scenario, and below it, less.
| Side by side | Wait until renewal | Break and take today's rate | Blend and extend |
|---|---|---|---|
| Rate | 5.40%, then 3.90% | 3.90% | 4.50% |
| Monthly payment | $3,055, then $2,724 | $2,696 | $2,837 |
| Penalty | None | $9,630 paid | Usually waived |
| Interest over 5 years | $93,002 | $79,476 | $92,072 |
| Paid over the window | $171,397 | $171,382 | $170,209 |
| Balance at the end | $371,606 | $367,724 | $371,863 |
| Cost: interest plus penalty | $93,002 | $89,106 | $92,072 |
All three run from today to the end of the new 5-year term. The wait path keeps your current payment until renewal, then resets it on the amortization left at the assumed rate. “Paid over the window” is every payment plus a penalty paid up front; paths that pay more also end with a smaller balance, which is why the cost row is the one to compare.
How the blended rate is worked out
(5.40% × 24 months + 3.90% × 36 months) ÷ 60 months = 4.50%
Your current rate for the months left in your term, today’s rate for the months added, averaged over the new term. No quoted rate entered, so the blend path uses this figure. Many lenders waive the penalty on a blend; some build part of it into the rate instead, and a quoted figure will show that.
Penalty to break today, estimated: $9,630, the interest rate differential against 4.33% (posted rate less your original discount, the bank method). Three months' interest would be $6,008.
Estimates based on the information entered, using monthly payments and the Canadian semi-annual compounding standard. Each path’s cost is the interest over the window plus any penalty, which is the same whether the penalty is paid or added to the mortgage. Discharge, legal and appraisal fees are not included, and your lender’s penalty and blended rate will differ; a written quote from your lender is the authoritative figure.
For informational purposes only — consult a licensed mortgage professional before deciding.
How the estimate works
The same window for all three
Each path runs from today to the end of the new term. Waiting means carrying on at your current rate and payment until your term ends, then renewing at the rate you assume for the rest of the window. Breaking and blending both start a new term today. Every payment is recalculated on the amortization you have left, so no path looks cheaper just by stretching the loan out.
The blended rate
The default is a weighted average: your current rate for the months left in your term, today’s rate for the months added, divided by the length of the new term. Many lenders waive the penalty on a blend; some build part of it into the rate instead. If your lender has quoted a figure, enter it and the calculator shows how far it sits from the weighted average.
The penalty
The break path uses the same penalty estimate as the break penalty calculator: for a fixed rate, the greater of three months’ interest and the interest rate differential, measured against posted rates less your original discount at a bank or credit union, or against the lender’s own rates elsewhere. For a variable rate, three months’ interest.
What to read with care
Each path’s cost is interest over the window plus any penalty. That figure treats a penalty paid in cash and one added to the mortgage the same way. The wait path depends entirely on renewal rates, which nobody knows, so try a few. Fees for discharge, legal work or an appraisal are not included, and a written quote from your lender is the only authoritative figure.
Common questions
- What is a blend and extend mortgage?
- A blend and extend is an arrangement with your current lender where the rest of your term is combined with a new one, usually starting today. Instead of paying a penalty to break, you get a single rate that blends your current rate with today's rate. It keeps you with the same lender and usually avoids a separate penalty, though the new rate is higher than you would get by breaking outright.
- How is a blended mortgage rate calculated?
- The usual starting point is a weighted average. Your current rate is weighted by the months left in your term, today's rate by the months being added, and the total is divided by the length of the new term. With 24 months left at 5.40% and a new five-year term at 3.90%, that is (5.40 × 24 + 3.90 × 36) ÷ 60, or 4.50%. Lenders' own figures often differ, because some use their posted rates or build part of the penalty into the blend.
- Is there a penalty for a blend and extend?
- Many lenders waive the penalty on a blend and extend, which is its main appeal. Some do not charge a separate penalty but build part of it into the blended rate instead, so the rate is higher than the simple weighted average. If you enter the rate your lender quotes, the calculator shows how far it sits from the weighted average, which gives a rough sense of how much of a penalty may be inside it.
- Is it better to blend and extend, break my mortgage, or wait for renewal?
- It depends on your numbers, and particularly on the penalty and on where rates are when your term ends. Breaking gets the lowest rate but costs a penalty; blending avoids the penalty but only part of the rate falls; waiting costs nothing now but depends on renewal rates nobody can know. The calculator compares all three over the same period so you can see which one the scenario shows as cheapest, and how sensitive that is to the rate you assume at renewal.
- Can I blend and extend a variable-rate mortgage?
- Blend and extend is mostly offered on fixed-rate mortgages. With a variable rate, many lenders let you convert to a fixed term without a penalty, which does a similar job more simply, and the penalty to break a variable mortgage is usually three months' interest rather than an interest rate differential. You may wish to check your contract or ask your lender which options apply to you.
- Is anything I enter stored or shared?
- No. The calculator runs entirely in your browser and nothing you type is sent to us.