Weigh Your Mortgage Refinance Costs Against Potential Savings

What happens when a mortgage is refinanced?

In a typical refinance, the existing mortgage is paid out and replaced with a new agreement. The new principal may include the remaining balance, any equity withdrawn, and—when permitted—some or all refinancing costs.

The borrower generally must qualify again. Lenders may review income, employment stability, credit history, existing obligations, and the property itself. An appraisal or another accepted valuation method may be required to determine available equity.

Refinancing at the end of a term may avoid an early‑payout penalty, but legal, registration, appraisal, and lender fees can still apply. Refinancing before maturity can trigger a substantial prepayment charge.

Why the mortgage payout quote matters

Closed mortgages commonly restrict how much principal can be repaid before the term ends. Paying out more than the permitted amount may trigger a prepayment penalty.

Fixed‑rate penalties may be calculated using three months’ interest or an interest‑rate differential (IRD). Some contracts apply whichever result is higher. IRD formulas vary significantly between lenders.

A lender may use posted rates, discounted comparison rates, remaining term, original rate discounts, or present‑value calculations. Two lenders can therefore produce different penalties for mortgages with similar balances and rates.

Variable‑rate mortgages often use a different penalty, commonly three months’ interest. Open mortgages may permit repayment without the same type of charge. The mortgage agreement always governs the actual penalty.

This calculator’s IRD estimate is intentionally simplified. When your lender provides a payout statement or written penalty quote, enter that amount in the override field. The Financial Consumer Agency of Canada explains common prepayment penalties and ways borrowers may reduce them.

How the simplified penalty estimate is calculated

The calculator first estimates three months’ interest on the outstanding balance. It then produces a simplified IRD using the difference between the current rate and the entered comparison rate over the remaining term.

When the mortgage is marked as closed, the model applies the larger of these two estimates unless a lender penalty quote is entered. This provides a cautious comparison but should not be described as the lender’s actual charge.

The comparison‑rate field is sensitive. A small change in that rate can materially affect the IRD result. Obtain the lender’s applicable comparison rate rather than selecting a convenient market rate.

Why monthly payment savings can be misleading

Simple break‑even divides upfront refinancing costs by the monthly payment reduction. For example, $6,000 of costs divided by a $250 reduction produces a simple break‑even of 24 months.

This shortcut is most meaningful when the current and new mortgages follow comparable repayment schedules. If a mortgage with 18 years remaining is replaced with a new 30‑year amortization, the payment may fall even though the borrower will repay the debt for much longer.

A smaller payment may also result from adding penalties and costs to the new principal. Those expenses have not disappeared—they have been financed and may accumulate interest.

For this reason, the calculator also compares remaining balances at the chosen horizon. Payments made during the period, upfront costs, and the ending balance provide a broader comparison than monthly cash flow alone.

Paying refinancing costs now or financing them

Paying penalties and closing expenses upfront requires more cash immediately but avoids increasing the new mortgage by those amounts. Financing the costs reduces the upfront requirement while increasing the secured principal.

Once a cost is added to the mortgage, interest may be charged on it for years. A $5,000 cost financed over a long amortization can ultimately cost more than $5,000 even though the original invoice has been paid.

The selected cost treatment affects the new mortgage amount, payment, loan‑to‑value ratio, and horizon comparison. Keep the treatment consistent when evaluating competing offers.

Equity withdrawal and the 80% LTV boundary

For a conventional residential refinance, 80% of the lender‑accepted property value is a commonly used maximum loan‑to‑value boundary. For a $650,000 accepted value:

$650,000 × 0.80 = $520,000

If the existing mortgage balance is $390,000, the theoretical difference is $130,000 before considering qualification, penalties, costs, and the proposed refinancing structure.

This does not guarantee that $130,000 can be withdrawn. The lender may accept a lower property value, impose a lower product limit, or approve less after reviewing income, credit, and debts.

Federal consumer guidance provides more information about borrowing against home equity .

Refinancing and the mortgage stress test

A borrower refinancing through a federally regulated lender generally must qualify using the applicable minimum qualifying rate. Under the current framework, the qualifying rate is commonly the higher of:

• the new contract rate plus two percentage points; or
• the prescribed minimum qualifying‑rate floor.

The calculator displays the mortgage payment produced by that rate. It does not calculate GDS or TDS ratios, verify income, or assess other obligations. The output is a qualifying‑payment illustration, not confirmation that the applicant passes the stress test.

Check the current OSFI minimum qualifying rate and the FCAC mortgage qualification guidance .

Use a comparison period that matches your plans

A refinance may look attractive over ten years but fail to recover its costs if the homeowner expects to sell after two. The comparison period should reflect how long the borrower reasonably expects to keep the new mortgage.

The horizon should not automatically match the new amortization. A five‑year comparison may be more useful when the offer has a five‑year term or when another transaction is likely within that period.

Because future rates are unknown, the model assumes that the entered rates continue for comparison. Actual renewal or variable rates may differ.

Questions to answer before refinancing

• What is the lender’s current written mortgage payout amount?
• How was the prepayment penalty calculated?
• Can the existing mortgage be ported to another property?
• Is a blend‑and‑extend option available?
• Which legal, appraisal, discharge and lender fees apply?
• Will the penalty and costs be paid upfront or financed?
• Does the payment fall because of the rate or because the amortization was extended?
• What mortgage balance will remain at the end of the new term?
• Which prepayment privileges and penalty method will apply to the replacement mortgage?

If your main objective is to explore equity availability, use the Canada home equity calculator . To examine the proposed repayment schedule in more detail, use the Canada mortgage calculator .