Blend and extend mortgage: how the blended rate works, and when it pays
Short answer: a blend and extend lets you renew early with your current lender without a prepayment penalty. The lender mixes your old rate with today's rate over the new term. On the Financial Consumer Agency of Canada's example, a 5.5% rate with 24 months left, blended with a 4% five-year rate, gives 4.6% for 60 months. You may still pay admin fees.
Blend and extend calculator
What would your blended rate be?
| Option over the new term | Monthly payment | Interest + penalty | Versus blend |
|---|
Blended rate uses the FCAC's simplified method. Payments use Canadian semi-annual compounding. "Break" adds an estimated penalty: the higher of 3 months' interest or a simple rate-gap (IRD) estimate, as in the FCAC's example. "Wait" assumes today's rate is still available at renewal. Excludes admin, appraisal and legal fees. Lenders' real formulas differ; ask yours for exact numbers.
How a blend and extend works
A closed mortgage locks your rate for the term. If rates fall halfway through, you have three choices: break the contract and pay a penalty, wait until renewal, or ask your lender to extend early and blend the rates. The FCAC describes the third option this way: lenders may allow you to extend your mortgage before the end of your term, you do not pay a prepayment penalty, you may pay administrative fees, and the lender blends your old rate with the new term's rate. Lenders also call it a blended mortgage.
The FCAC publishes a simplified way to estimate the blended rate. It is a weighted average by months:
- Multiply your current rate by the months left in your current term.
- Subtract the months left from the months in the new term.
- Multiply today's rate by that difference.
- Add the results of steps 1 and 3.
- Divide by the months in the new term.
The logic: for the months you were already committed to, you keep paying roughly your old rate. Only the extra months get today's rate. That is why a blend lands between the two rates, and why it moves closer to today's rate the less time you have left.
One thing the simplified method does not capture: your lender's real formula, which can differ from the FCAC's simplified illustration. The FCAC says your lender must tell you how it calculates your new rate, so ask for the method and compare it with the estimate above.
Worked example: the FCAC's numbers, step by step
Using the FCAC's own scenario: a $200,000 balance, 22 years of amortization left, a 5.5% rate, 24 months left in the term, and a lender offering 4% for a new five-year (60-month) term.
- Step 1: 5.5 × 24 = 132
- Step 2: 60 − 24 = 36 months
- Step 3: 4 × 36 = 144
- Step 4: 132 + 144 = 276
- Step 5: 276 ÷ 60 = 4.6% for the next 60 months
What it does to the payment, using semi-annual compounding over the 22 years left: at 5.5% the monthly payment is $1,300.54. At the blended 4.6% it is $1,201.01, about $99.53 less a month. At a clean 4% it would be $1,136.83.
Blend vs break vs wait: the same 60 months
To compare fairly, count interest plus any penalty over the same 60 months. We used the FCAC's simple penalty approach: the higher of three months' interest ($200,000 × 5.5% ÷ 4 = $2,750) or a rate-gap estimate ($200,000 × 1.5% × 24 ÷ 12 = $6,000). So the estimated penalty is $6,000.
| Option | Payment | Interest + penalty, 60 months |
|---|---|---|
| Blend and extend at 4.6% | $1,201.01 | $42,367 |
| Break, pay $6,000, take 4% | $1,136.83 | $36,701 + $6,000 = $42,701 |
| Wait: 24 months at 5.5%, then 36 at 4% | $1,300.54, then $1,148.24 | $42,733 |
In this example the three options land within about $370 of each other, and the blend edges ahead before fees. That is the honest takeaway: a blend and extend is rarely a jackpot. It mostly turns a lump-sum penalty into a slightly higher rate spread over time, with a lower payment starting now. The gap gets bigger when the penalty is large relative to the rate drop, or when your lender's blend formula is less generous than the FCAC's estimate. Run your own numbers in the calculator above.
What if rates went up instead?
The same formula works in reverse. Say your rate is 4% with 24 months left, and your lender's five-year rate today is 5.5%. Step 1: 4 × 24 = 96. Step 3: 5.5 × 36 = 198. Step 4: 96 + 198 = 294. Step 5: 294 ÷ 60 = 4.9%. That is higher than your current 4%, but lower than the 5.5% you would face if you renewed at today's rate. In a rising rate market, the question flips: is locking in 4.9% for five years now better than keeping 4% for two years and taking whatever the rate is at renewal? Nobody knows where rates go, so treat it as a trade between certainty and cost, and compare the payment you can carry in each case.
What to ask your lender before you sign
- "Show me how you calculated the blended rate." The FCAC says the lender must tell you.
- "What fees apply?" Admin, appraisal or legal fees can eat a thin saving.
- "What would breaking cost today?" Banks have penalty calculators on their sites. See our mortgage penalty guide for how IRD works.
- "Can I use my prepayment privilege first?" A lump sum lowers the balance every option applies to. Our prepayment privileges guide has the math.
- "When is my new renewal date?" A blend extends your term, so renewal moves later. That helps if rates rise and costs you if they keep falling.
Your options, side by side
| Option | Upfront cost | When people pick it |
|---|---|---|
| Blend and extend | Possible admin fees, no penalty | Want a lower payment now and to stay with the lender. |
| Break and re-sign | Prepayment penalty plus fees | Large rate drop, small penalty, or a better offer elsewhere. |
| Wait for renewal | $0 | Little time left in the term, or the penalty is large. |
When your renewal does come, the mortgage renewal guide covers the 21-day statement and how to compare offers. Thinking about fixed or variable for the new term? See variable vs fixed. More calculators are on the tools page.
Questions people ask
What is a blend and extend mortgage?
It is an early renewal option where your lender extends your mortgage before the term ends and blends your current rate with the rate for the new term. The FCAC says you do not pay a prepayment penalty with this option, though you may pay administrative fees.
How is a blended mortgage rate calculated?
The FCAC's simplified method: multiply your current rate by the months left in your term, multiply today's rate by the remaining months of the new term, add the two and divide by the months in the new term. 5.5% for 24 months plus 4% for 36 months gives 4.6% over 60 months.
Is blend and extend better than breaking my mortgage?
It depends on the size of your prepayment penalty, the fees, and the rate gap. Breaking gives you the full new rate but costs a penalty; blending avoids the penalty but gives you a higher rate. Compare total interest plus fees over the same period before choosing.
Does my lender have to explain how it blends the rate?
Yes. The FCAC says your lender must tell you how it calculates your new interest rate. Ask for the calculation in writing and compare it with the simplified method.
Can I blend and extend with a different lender?
No. A blend and extend is offered by your current lender, because it extends your existing contract. Moving to another lender means breaking or waiting until renewal.
Does a blend and extend help if rates went up?
It can work in reverse. If today's rate is higher than yours, the blended rate will be higher than your current rate, but lower than today's rate.
Looni's countdown tracks your term and renewal date, and the calculators let you test blend, break and wait with your own numbers. Read-only, no advice, just the arithmetic.
Sources
Financial Consumer Agency of Canada, Breaking your mortgage contract (blend-and-extend definition, no penalty, admin fees, lender must explain the calculation, the 5.5% / 4% / 4.6% example and its five steps) and Mortgage fees: Prepayment penalties (3 months' interest or IRD, penalty calculators). Payment figures computed by Looni with semi-annual compounding.