Blend-and-extend calculator: your blended rate vs breaking
A blend-and-extend renews your mortgage early with no prepayment penalty; the new rate mixes your old rate for the time left with today's rate for the extra time. 5.39% with 30 months left, extended to a new 5-year term at 4.58%, blends to about 4.99%. Over the new term that costs $96,891 in interest and fees, against $96,233 to break and $97,081 to wait.
Blend-and-extend calculator
Estimate the blended rate, then see if it beats breaking or waiting.
Cost over 5 years
| Measure | Stay until renewal | Break and refinance now | Blend and extend |
|---|---|---|---|
| Cost | $97,081 | $96,233 | $96,891 |
| First monthly payment | $2,705 | $2,518 | $2,611 |
Estimate, not advice. Educational estimate only, not financial, mortgage, tax or legal advice. Lenders, insurers and governments set their own rules and can change them; confirm with a licensed professional before you decide.
Estimated blended rate 4.99%. Over 5 years: stay $97,081, break $96,233, blend $96,891.
Assumptions & sources
Assumptions
- Blended rate = (your rate × months left + today's rate × extra months) ÷ new term in months. Lenders may use their posted rates or other methods.
- Refinance fees $2,000 (our estimates) and an estimated penalty unless you enter a quote.
Sources
- Financial Consumer Agency of Canada — Breaking your mortgage contract (fees, cash-back clawback, blend-and-extend) (effective October 15, 2025). Checked .
- Financial Consumer Agency of Canada — Reduce mortgage prepayment penalties (3 months' interest or the IRD; posted-rate method; prepayment privileges; porting) (effective October 15, 2025). Checked .
How this tool works
The estimate weights each rate by the months it covers. Lenders use their own methods (FCAC says they must tell you how), so enter your quote when you have it. If the quote is far above the estimate, the penalty may be built into the rate. The full model with cash out and a HELOC is on the home page.
Frequently asked questions
How is a blend-and-extend rate calculated?
Commonly as a time-weighted average: your current rate for the months left plus today's rate for the extra months, divided by the new term. Lenders may use posted rates or add a margin; ask for the calculation.
Is blend and extend better than breaking my mortgage?
It avoids the penalty but keeps part of your old rate. When the penalty is large (a big-bank IRD) blending often wins; when it's only three months' interest, breaking can be cheaper.
Primary sources
- Financial Consumer Agency of Canada — Breaking your mortgage contract (fees, cash-back clawback, blend-and-extend) (effective October 15, 2025). Checked .
- Financial Consumer Agency of Canada — Reduce mortgage prepayment penalties (3 months' interest or the IRD; posted-rate method; prepayment privileges; porting) (effective October 15, 2025). Checked .