How much will it cost to break my mortgage in Calgary?
Selling, refinancing or switching lenders before maturity can cost a few thousand dollars, or much more. Here is how the number is built, with examples on Calgary prices.
Short answer
On a fixed-rate mortgage, the lender charges the higher of two amounts: three months' interest or the interest rate differential (IRD), which compares your rate with today's rate over the time left in your term (FCAC). Calgary example: on the city's median sale price ($562,500, CREB, October 2026) financed at 80%, or $450,000, at 5.58% while the reference rate is 4.58%, breaking 30 months before maturity costs about $11,250 (IRD), versus $6,278 for three months' interest. At maturity there is no penalty; after 5 years on a longer term, the law caps it at three months' interest.
In Calgary, the median home sold for $562,500 in October 2026 (CREB, City of Calgary). With 20% down, that leaves a mortgage of about $450,000. That is the balance used in the examples below: replace it with yours. The penalty often surprises people who sell or refinance mid-term, yet it can be calculated in advance.
The two formulas, and which one applies
According to the Financial Consumer Agency of Canada (FCAC), on a fixed-rate mortgage the lender generally charges the higher of two amounts:
- Three months' interest on the balance: balance × rate ÷ 12 × 3. That is the floor.
- The interest rate differential (IRD): the gap between your rate and today's rate for a comparable term, applied to the balance for the time left in the term. Lenders use it when your rate is higher than today's rate and you signed less than 5 years ago.
One key point: depending on the contract, the comparison may use your original rate or the posted rate at signing. A lender that works from the posted rate, rather than the discounted rate you actually got, often ends up with a much larger IRD. On a variable rate, check your contract's clause: it often sets the penalty at three months' interest.
The Calgary example, in numbers
Payotte calculation. Published assumptions: balance of $450,000 (80% of the median price), contract rate of 5.58%, today's rate for a comparable term of 4.58% (Bank of Canada 5-year fixed reference rate, August 2026), so a one-point gap.
| Time left in the term | Three months' interest | IRD | Penalty charged |
|---|---|---|---|
| 48 months | $6,278 | $18,000 | $18,000 |
| 30 months | $6,278 | $11,250 | $11,250 |
| 12 months | $6,278 | $4,500 | $6,278 |
| 3 months | $6,278 | $1,125 | $6,278 |
Simplified estimate, for illustration only. Each lender applies its own method (posted or discounted rate, rounding of terms). Always ask your lender for the calculation in writing before deciding.
Why the time left changes everything
The IRD grows with two things: the rate gap and the number of months left in the term. Each remaining month adds about "balance × gap ÷ 12" to the bill: here, close to $375 a month. Early in a 5-year term, the IRD dominates; near maturity it melts away and the three-month floor applies. And if rates have risen since you signed, there is no IRD: you pay three months' interest.
The Interest Act's 5-year rule
For a mortgage with a term longer than five years, section 10 of the Interest Act lets you pay it off after five years with the balance plus three months' interest, and no other penalty. The rule does not cover terms of 5 years or less: for those, the contract sets the calculation.
Four ways to lower it
- Your prepayment privileges. Most contracts let you pay down part of the balance each year with no penalty. Using them before breaking lowers the balance the penalty is calculated on.
- Portability. If you sell to buy again, a portable mortgage moves to the new home, often with no penalty.
- Timing. Since the IRD shrinks every month, waiting a few months can change the math completely.
- Negotiating with the same lender. A refinance or a blend-and-extend with your current lender can replace the penalty with a blended rate.
Each one depends on the clauses in your contract. That is exactly what I check with my clients before a decision that cannot be undone. You can see my Payotte profile or compare with the other verified professionals in Calgary.
Frequently asked questions
How much does it cost to break a fixed-rate mortgage?
The higher of three months' interest or the interest rate differential (IRD). On a $450,000 balance at 5.58%, three months' interest is $6,278; if today's rate is one point lower and 30 months are left in the term, the IRD is about $11,250 and that is the amount charged.
How is the interest rate differential (IRD) calculated?
Simplified: balance × (your rate − today's rate for a comparable term) × years left in the term. The FCAC notes that, depending on the contract, the lender may compare with your original rate or with the posted rate at signing, which is why two lenders do not give the same number. Ask for the calculation in writing.
Is there a penalty at the end of the term?
No. At maturity you can pay off, renew or switch lenders with no penalty. That is why timing a sale or a refinance with your maturity date often saves thousands of dollars.
Is the penalty capped after 5 years?
Yes, for a mortgage with a term longer than 5 years: section 10 of the Interest Act lets you pay off after five years with no more than three months' interest. It does not apply to terms of 5 years or less.
How can I lower my mortgage penalty?
Use your prepayment privileges first (they lower the balance the penalty is calculated on), check whether the mortgage is portable when you sell and buy, wait for the remaining term to shrink, or negotiate a blend-and-extend with the same lender. Each one depends on your contract.
Sources consulted November 9, 2026: FCAC, reduce prepayment penalties · Interest Act, s. 10 · CREB, City of Calgary monthly statistics, October 2026 · Bank of Canada, 5-year fixed reference rate (August 2026)