Variable vs Fixed Rates in Canada: How Each One Reprices, and the Risk You Take

A fixed rate is locked when you sign and holds for the term, so the lender carries the risk of rates moving. A variable rate is priced as a spread over the lender's prime rate and reprices whenever that prime changes, so you carry that risk. Neither is automatically cheaper — the real difference is who absorbs the surprise, and whether your budget can.

What prime rate actually means

Prime is a benchmark each lender sets for itself. It is not the Bank of Canada's policy rate, but the two move together: when the Bank adjusts its policy rate, lenders generally move prime in the same direction and by a comparable amount. The Bank publishes the policy rate and related benchmark rates on its rates page, and that is where most of the movement in Canadian borrowing costs starts.

Your own personal interest rate is not prime. It is prime plus or minus a spread, and that spread is priced off your file:

• credit history, and how actively you have used credit recently;
• income stability, and how much of that income is already committed to debt;
• down payment or home equity, and the type of property involved;
• the term you choose, and whether the rate is locked or floating;
• how much other debt you carry relative to your income.

This is why two people at the same lender, sitting under the same prime rate, can be quoted different numbers. It is also why the benchmark is only half of any comparison. A deep discount off a higher prime can still cost less than a shallow discount off a lower one. When you compare mortgage finance rates, compare the spread first and the monthly payment second.

How a fixed rate is set, and what you give up

Fixed rates are priced off funding costs and bond yields at the moment you lock in, then held for the term. Your payment becomes predictable and the lender absorbs the cost if wholesale rates rise above what it quoted you. If rates fall, you keep the rate you signed — the trade is symmetrical, and it is the reason fixed pricing usually starts higher than variable pricing on the same term.

Canadian fixed-rate mortgages are compounded semi-annually by law, which affects how your effective annual cost is calculated rather than the headline number you are shown. The Financial Consumer Agency of Canada explains how mortgages are structured and what lenders must disclose to you.

The trade-off is the exit cost. Because the lender has committed to a price for the term, breaking that commitment early is priced accordingly, and fixed-rate prepayment penalties are calculated on a different basis than variable ones — frequently using the larger of two methods. That single clause can decide whether a fixed rate was genuinely the cheaper choice, so read it before you sign, not when you sell.

How a variable rate reprices

A variable quote usually looks like prime minus a spread. The spread is normally fixed for the term; the prime is not. When prime moves, your cost moves with it, in full, with no phase-in.

What happens next depends on which variable product you hold:

• Adjustable-payment mortgage: the payment itself moves. Your monthly obligation changes as prime changes, so budgeting is the thing you are actively managing.
• Fixed-payment variable mortgage: the payment stays constant while the interest-and-principal split changes. When prime rises, more of each payment is absorbed by interest and less reaches principal, so the loan pays down more slowly and the amortization stretches. If rates rise far enough for long enough, the payment eventually has to be reset upward.
• Variable-rate line of credit: the minimum payment is often interest-only, so a prime increase raises your required payment roughly in proportion to the balance. This is the most direct repricing exposure in a typical household.

Estimating your own exposure is simple arithmetic: multiply your balance by the rate change expressed as a decimal, then divide by twelve for a monthly figure. That tells you what a given move costs before you decide whether you can live with it.

Side by side

How to judge the risk you are actually taking

1. Price the move, not the forecast. Apply the arithmetic above to your own balance. If the resulting payment is uncomfortable, your problem is the product, not the prediction.
2. Count how much of your debt reprices together. If a mortgage, a line of credit and a variable personal loan all float off prime, that is one bet placed three times. Increases land on all of them in the same month.
3. Match the term to your plans. Shorter terms mean more renewal events and more chances to reprice. If you might move, renovate with borrowed money, or sell within a few years, the exit cost matters more than a fraction of a point.
4. Find out what buffer already exists. Federally regulated lenders generally work to a total debt service ratio ceiling of about 44% and apply a qualifying stress-test rate above the contract rate under Guideline B-20. You were approved at a higher rate than you will initially pay — useful, but that is the lender's threshold, not your emergency fund.
5. Weigh your own income risk. A variable payment is easier to carry on stable or rising income. Commission-based, contract and single-income households should weight that more heavily.
6. Read the prepayment clause. It is where the real cost difference between the two products usually hides.

Personal loans and lines of credit follow the same logic

Fixed versus variable is not only a mortgage question. Many instalment loans are fixed-rate: you know the payment and the payoff date, and the lender carries the rate risk. Others are priced off prime and can reprice. Credit cards are a third category — most carry a contractual rate that does not track prime, so a rate cut does not reach them.

Lines of credit are the clearest case, and home equity lines of credit are the largest version of it. At federally regulated lenders, home equity lines of credit are generally limited to 65% of appraised property value, with total secured lending against the property usually capped at 80%. That is a regulatory ceiling, not a statement about how much debt is sensible. A variable-rate line of credit reprices immediately when prime moves, and because the minimum payment is often interest-only, the increase arrives in full.

There is a legal ceiling, and it sits far above normal pricing

The Criminal Code criminal rate of interest is 35% per year under section 347, calculated using a defined method that aggregates interest and certain charges. It is an outer legal limit, not a target or a benchmark. Any mainstream mortgage or instalment loan that approaches it is not competing on price — it is a signal that something about the product or the file has gone badly wrong.

Questions worth asking before you sign

• What is your prime rate today, and what spread am I being quoted against it?
• If prime moves, does my payment change, my amortization change, or both?
• How is the prepayment penalty calculated, and what would it be a year from now?
• Is the rate held until closing, and for how long?
• Are there fees outside the rate — appraisal, discharge, administration?

Before any of that, check your own file. Canada has two national credit reporting bureaus, Equifax Canada and TransUnion Canada, and a free copy of your credit report is available from each. Both should be reviewed, because a lender or insurer may pull from either.

If a problem arises later, complaints about federally regulated financial institutions are handled by the Financial Consumer Agency of Canada. Provinces license and supervise most other lenders, and each has a consumer protection office. Keep your disclosure documents — they are the record of what you were actually promised.

Significant borrowing decisions depend on individual circumstances, and regulated professional advice is appropriate when the amounts involved are large or your income is uncertain.

loanwolf.ca is a matching service, not a lender. It does not make loans, set rates or make credit decisions, and the lowest advertised rates are only ever available to the most qualified applicants — so the rate you are offered will reflect your own file, not a headline figure.