Fixed vs Variable Mortgage

With a fixed-rate mortgage, the contractual interest rate stays the same for the selected term. With a variable-rate mortgage, the contractual rate can move during the term, usually in relation to the lender's prime rate or another stated benchmark. The first question is therefore not which rate is cheaper today, but what can change after closing and who carries that risk.

A variable mortgage also needs one more distinction. Some products adjust the payment when rates move; others may keep the payment unchanged for a time and change how much of each payment goes to interest versus principal. A fixed-versus-variable comparison that ignores that difference is incomplete.

The decision is therefore both mechanical and strategic: how the product behaves, how much payment or balance uncertainty the household can absorb, how long the mortgage is likely to be kept, and what it could cost to leave early.

Fixed and variable are not always an all-or-nothing choice. FCAC describes a hybrid or combination mortgage where one portion of the mortgage carries a fixed rate and another portion carries a variable rate. The fixed portion provides some protection if rates rise, while the variable portion preserves some benefit if rates fall.

That can reduce concentration in one rate outcome, but it also creates more moving parts. The portions may have different terms, maturity dates or renewal decisions. FCAC notes that this complexity can make a hybrid mortgage harder to transfer to another lender.

A hybrid structure should therefore be compared as two linked mortgage components, not as one blended headline rate. Ask what happens to each portion if you sell, refinance, switch lenders or reach maturity at different times.

The simplest resilience test is to hold the mortgage amount and amortization constant and change only the interest rate. The table below uses an illustrative $600,000 mortgage with a 25-year amortization and monthly payments under the standard Canadian residential-mortgage compounding convention. It is not a rate forecast or lender quote.

A borrower considering an adjustable-payment variable mortgage should be comfortable not only with the starting payment but with plausible higher payments. A fixed-rate borrower avoids that within-term payment movement, but still faces a new rate when the term ends.

A comparison that labels everything simply 'variable' is incomplete. In an adjustable-payment variable mortgage, the payment typically moves with the rate. The cash-flow shock is visible quickly, but the payment adjustment helps keep principal repayment closer to schedule.

In a fixed-payment variable mortgage, the payment may initially stay unchanged while the interest portion rises and the principal portion falls. If rates rise enough, the mortgage can reach contractual trigger mechanics and the remaining amortization can move away from the original path.

If this distinction is new, read Fixed-Payment Variable vs Adjustable-Rate Mortgage before choosing a variable product.

Some variable mortgage contracts allow the borrower to convert to a fixed rate during the term. That can be useful, but it should not be treated as a guarantee that today's fixed-rate alternative will still be available later.

The conversion rate, remaining or replacement term and other conditions are lender- and contract-specific. If rates have already risen by the time the borrower wants certainty, the available fixed rate may also be higher.

Treat conversion as a backup feature to understand, not as the reason a household accepts variable-rate risk that it could not otherwise afford.

A five-year rate comparison can be misleading if the borrower is likely to sell, refinance or restructure in year two or three. In that situation, the expected holding period may matter as much as the rate.

Closed fixed mortgages can use penalty formulas that become significant depending on the lender, contract, remaining term and comparison-rate methodology. Variable products can have different penalty mechanics, but those also have to be confirmed rather than assumed. Use the Mortgage Penalty Calculator as an estimate and obtain lender-specific payout information before acting.

A Burlington client in our funded-file library ultimately refinanced even after including the prepayment penalty. The file does not prove that one rate type is better; it shows why break cost belongs inside the rate decision from the beginning.

A fixed mortgage is often described as 'safe' because the rate is known during the term. That is useful certainty, but it does not eliminate repricing risk. At maturity, the remaining balance usually needs a new term and a new rate. If market rates are higher then, the renewal payment can increase sharply.

Variable borrowers experience some rate movement during the term. Fixed borrowers can experience a larger step-change at renewal. Neither pattern is automatically better; they distribute the timing of rate risk differently.

Use Mortgage Term vs Amortization to project the balance that will still exist when the fixed or variable term ends, then use the Mortgage Renewal Calculator to stress that balance at several future rates.

Instead of asking only 'Where are rates going?', score the decision against five forms of risk. The correct answer can change even when two borrowers have identical incomes and mortgage amounts because their future plans and tolerance for uncertainty are different.

Fixed can be attractive when the household has little room for payment increases, values a known budget, expects to keep the mortgage for the chosen term and is comfortable giving up immediate benefit if variable rates fall.

It can also be reasonable where a business owner, investor or family wants to remove one source of uncertainty from an already-variable income or expense picture. But certainty should not be purchased blindly: compare the contract's prepayment privileges and break methodology if there is a meaningful chance the mortgage will not survive the full term.

Variable can be attractive when the borrower has meaningful cash-flow room, understands the product's payment mechanics, can tolerate rate increases and prefers to remain exposed to falling rates during the term rather than waiting for renewal.

The decision is stronger when it remains affordable even if rates do not fall on schedule. Choosing variable only because a forecast predicts cuts converts a household mortgage into a one-way bet. The Variable vs Fixed Calculator should therefore be run with an adverse path as well as a favourable one.

A Toronto funded file illustrates a related principle. The clients needed equity for tuition, but a full refinance was not recommended because the existing first mortgage had a very low rate and a high break penalty. A second-position HELOC supplied the new money while the first mortgage stayed intact.

This does not tell a borrower to preserve every old mortgage. It shows why a rate decision is often really a whole-balance decision: what happens to the rate, penalty and flexibility on every dollar if the existing mortgage is replaced?

The strongest comparison makes the household survive several plausible futures before choosing the product that feels best in one of them.