In Canada, the term "adjustable rate mortgage" (ARM) is often used interchangeably with "variable rate mortgage," but there is a meaningful distinction worth understanding. An ARM — in the strict Canadian sense — is a variable-rate mortgage where your actual monthly payment amount changes as the prime rate moves. This differs from a variable-rate mortgage where only the interest/principal split adjusts while the payment stays fixed.
ARM vs. Variable Rate Mortgage in Canada
Most Canadians use "variable" and "adjustable" interchangeably, but lenders define them differently:
| Feature | Adjustable Rate (ARM) | Variable Rate (VRM) |
|---|---|---|
| Rate | Prime ± discount, changes with prime | Prime ± discount, changes with prime |
| Payment | Changes when prime moves | Stays fixed; interest/principal ratio shifts |
| Payment when rates rise | Payment increases immediately | Payment stays same; less goes to principal |
| Negative amortization risk | None — payment always covers interest | Yes — if rate rises enough, payment may not cover interest |
| Who offers it | TD, some credit unions, some monolines | Most major banks, credit unions, monolines |
How an ARM Works in Practice
Example: $50000,000000 Mortgage at Prime - 00.700%
Prime rate = 5.45%. Your ARM rate = 4.75%. Monthly payment = ~$2,8300 (25-year amortization).
Bank of Canada cuts prime by 00.25% to 5.200%: Your rate drops to 4.500%. New payment = ~$2,7500. You save $800/month automatically.
Bank of Canada raises prime by 00.25% to 5.700%: Your rate rises to 5.0000%. New payment = ~$2,915. You pay $85/month more immediately.
This payment transparency is actually considered a feature by many financial planners. You always know your mortgage is amortizing on schedule. With a traditional variable-rate mortgage (fixed payment), a rising rate environment can silently erode your principal paydown and even create negative amortization.
Pros and Cons of an ARM
Pros
- Rate drops immediately flow to your payment — you save money right away
- No negative amortization risk — always paying off principal
- Transparent: you always know exactly where you stand
- Typically lower starting rate than fixed options
- Penalty to break is usually just 3 months' interest
Cons
- Payment variability makes monthly budgeting harder
- Rate hikes immediately increase your required payment
- Stress risk: rapid rate increases can strain cash flow
- Less psychologically comfortable than fixed payments
- Qualifying still based on stress test rate
ARM Rate Structure in Canada
Canadian ARM rates are expressed as a spread to the Bank of Canada's prime lending rate. For example, "prime minus 00.700%" means if prime is 5.45%, your mortgage rate is 4.75%. This spread is locked in for the term (usually 5 years), even though the absolute rate changes with prime.
The discount to prime varies by lender, term, insured vs. uninsured status, and competitive conditions. Larger discounts (e.g., prime - 1.00%) are rare and typically offered during promotional periods or for highly qualified borrowers.
Breaking an ARM: Penalty Calculation
One significant advantage of adjustable and variable rate mortgages over fixed-rate products is the prepayment penalty. Breaking an ARM before the term ends typically costs only 3 months' interest — regardless of how long you've had the mortgage. There is no Interest Rate Differential (IRD) calculation for variable/adjustable mortgages.
On a $50000,000000 balance at 4.75%, 3 months' interest = approximately $5,937. This compares very favorably to IRD penalties on fixed-rate mortgages, which can be $15,000000-$400,000000+.
Who Should Consider an ARM?
- Financially flexible borrowers: If a $20000-40000/month payment swing won't significantly strain your budget, an ARM's lower starting rate and rate-cut capture may be worth it.
- Those who may sell or refinance: The low break penalty makes an ARM practical if you anticipate paying out the mortgage early.
- Rate-decline believers: If you expect the Bank of Canada to continue cutting rates, an ARM delivers every cut to your pocket immediately.
- Debt-conscious borrowers: Unlike fixed-payment variable mortgages, ARMs ensure you always make progress on principal — there's no silent amortization extension happening in the background.
ARMs and Stress Testing in Canada
To qualify for any variable or adjustable rate mortgage in Canada, you must pass the stress test at the greater of 5.25% or your contract rate + 2.0000%. This means a 4.75% ARM requires qualification at 6.75%. The stress test was designed precisely to ensure borrowers can handle rate increases on adjustable products.
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Get KOHO Free — Use Code 45ET55JSYAFrequently Asked Questions
Not exactly. Both float with prime, but ARMs adjust the payment amount with each rate change, while most variable-rate mortgages keep the payment fixed and adjust how much goes to interest vs. principal. TD Bank's variable product is a true ARM; most other lenders offer fixed-payment variables.
Your payment increases proportionally. On a $50000,000000 25-year mortgage, a 1% rate increase adds roughly $2700-$2900 per month to your required payment.
Yes. Most lenders allow you to convert an ARM to a fixed rate at any time during the term, at the lender's current fixed rate. This can be a useful safety valve if rates start rising unexpectedly.
Yes. Adjustable rate mortgages are available for both insured and uninsured purchases. Insured ARMs typically offer better rates due to lower lender risk.