Breaking a closed fixed-rate mortgage early costs the greater of two numbers: three months’ interest, or the interest rate differential (IRD) — and when rates have fallen since you signed, the IRD is usually the bigger one. Variable-rate closed mortgages typically cost three months’ interest, and open mortgages can be repaid anytime without penalty, which is why they carry a higher rate. Before you list, refinance, or sign anything, get your lender’s exact payout figure — that number, not any estimate, governs. See three months’ interest vs IRD: which one applies to you.

Most borrowers are quoted a penalty only after they have committed to the move. Run the number first, and the decision — sell now or at renewal, refinance or wait — often changes.

How is a fixed-rate mortgage penalty calculated?

For a closed fixed-rate mortgage, the penalty is the greater of:

• (a) Three months’ interest on your remaining balance at your contract rate, or
• (b) The interest rate differential (IRD) — roughly, (your contract rate minus the lender’s current rate for your time remaining) × remaining balance × time remaining.

Whichever is larger is what you pay. Early in a term the IRD usually dominates; in the final months, three months’ interest often wins — which is why timing a move near renewal can save real money. If your renewal is close, start with a Mortgage Renewal Check before pricing any break.

Why are big-bank IRD penalties so much larger?

The comparison rate is the trap. Many big banks calculate the IRD using their posted rates rather than discounted rates. At signing you received a discount off the posted rate — and in the penalty calculation, that discount effectively inflates the differential between your contract rate and the comparison rate.

Monoline lenders, which do not publish the same posted-rate structure, typically produce a much smaller differential on an identical balance and timeline. The same homeowner can owe dramatically different penalties depending on which type of lender holds the mortgage — one of the strongest reasons to discuss penalty math before choosing a lender, through a Pre-Approval & Refinance Check, not just when leaving one.

“Great rates, fast closing, and excellent customer service.” — Madhav Dhakal, Google review

What does an IRD penalty look like in real numbers?

Illustration only — arithmetic with round numbers, not a quote. Take a $400,000 balance, a 5.00% contract rate, a 3.50% comparison rate, and 3 years remaining:

• Differential: 5.00% − 3.50% = 1.50%
• IRD: 1.50% × $400,000 × 3 years ≈ $18,000
• Three months’ interest: $400,000 × 5.00% ÷ 4 ≈ $5,000
• Penalty = the greater of the two ≈ $18,000

Your lender’s calculation uses its own comparison term, exact days remaining, and posted-rate schedule, so your figure will differ — possibly by a lot. Use illustrations to understand the math, never to budget a payout.

How can you reduce or avoid the penalty?

• Port the mortgage. Buying another home? Porting your rate and term to the new property can avoid the penalty entirely, subject to qualification and timing rules that vary by lender. See porting: the penalty-free way to keep your rate when you move.
• Use prepayment privileges first. Before a planned sale, use your annual lump-sum and payment-increase privileges — commonly 10–20% per year, but they vary by lender, so confirm yours — to shrink the balance the penalty is calculated on.
• Time it to renewal. A penalty with months remaining is far smaller than one with years remaining; sometimes a short delay changes the decision.
• Get the exact payout statement. Only your lender’s figure governs. Ask for it in writing, note how long it is valid, and bring it to your broker before signing anything.

Another way to stay put is blend-and-extend: averaging today’s rate instead of breaking.

Thinking about breaking your mortgage? Call me with your lender’s payout figure and we will run the port, prepay, and wait options side by side. Call (780) 722-5621.

By Travis Bannert, Realtor and Mortgage Broker

Travis Bannert, Mortgage Broker | Next Door Mortgages, Dominion Lending Centres | (780) 722-5621 | nextdoormortgages.com