Two Kinds of "Variable" — Only One Has a Trigger
Canada sells two quite different products under the "variable rate" label. An adjustable-rate mortgage (ARM) moves your payment every time prime moves — rate up, payment up, amortization stays on schedule. A static-payment variable (VRM) keeps your payment fixed while the rate floats underneath it: when prime rises, more of your unchanged payment goes to interest and less to principal.
The static-payment design feels safer — your cash flow never jumps. But it carries a mechanism the adjustable version doesn't: if rates rise far enough, your fixed payment eventually can't even cover the monthly interest. The rate at which that happens is your trigger rate.
Trigger Rate vs. Trigger Point
Trigger rate is where your payment equals the interest portion — nothing is left for principal. Past it, unpaid interest gets added to your balance and the mortgage amortizes negatively: you owe more each month despite paying on time.
Trigger point comes later, when the growing balance crosses a contractual ceiling — commonly the original principal amount, or 105% of the home's value on insured mortgages. At the trigger point the lender must act, and so must you.
A quick approximation: (your monthly payment × 12) ÷ your current balance. If you pay $2,400/month on a $520,000 balance, your payment covers interest up to roughly 5.5%. Your lender can give you the exact figure — it's worth a call to get it, since the precise number depends on your payment frequency and compounding.
What Actually Happens If You Hit It
You won't get a foreclosure letter — you'll get options, and the earlier you choose one, the cheaper it is:
Raise the payment. Even a modest voluntary increase can push you back above the trigger and restart principal paydown. Most lenders allow payment increases without penalty.
Make a lump-sum prepayment. A smaller balance lowers the interest portion, moving your trigger rate further away.
Convert to fixed. Most variable products allow penalty-free conversion into a fixed term — usually of at least the remaining length. This locks certainty, at whatever fixed rates are on offer that day; it's a decision to price, not a reflex.
Restructure at renewal. If negative amortization has stretched your effective payoff timeline, renewal is where the amortization gets trued back up — often meaning a noticeably higher payment. Planning for that jump beats being surprised by it.
| Adjustable (ARM) | Static-payment variable (VRM) | |
|---|---|---|
| Payment when prime rises | Increases immediately | Unchanged |
| Amortization when prime rises | Stays on schedule | Silently extends |
| Trigger rate risk | None | Yes — payment can stop covering interest |
| Where the pain lands | Monthly cash flow, immediately | Balance and renewal payment, later |
Why Everyone Learned This Word in 2022
When the Bank of Canada raised its policy rate from 0.25% to 5% between March 2022 and mid-2023, a large share of static-payment variable mortgages — priced at pandemic lows — blew through their trigger rates. Borrowers who'd never heard the term discovered their balances were growing. The episode is the clearest argument for knowing your trigger rate before the rate cycle turns, not after.
The lesson isn't "variable is dangerous" — variable-rate borrowers have done well across most historical periods, and the 3-months'-interest penalty is a real advantage. The lesson is that the static-payment structure trades visible pain (payment jumps) for invisible pain (amortization drift), and invisible pain requires you to actually look.
If You Hold a Static-Payment Variable Today
Three numbers to know: your current rate, your trigger rate, and your balance versus original principal. If the gap between your rate and trigger rate is under about one percentage point, decide your response to the next hike now — raise the payment, prepay, convert, or consciously accept the drift. Any of these can be right; drifting into the trigger point unaware is the only wrong answer.
Frequently Asked Questions
Does my fixed-rate mortgage have a trigger rate?
No. Trigger rates only exist on variable-rate mortgages where the payment stays fixed while the rate floats. Adjustable-rate variables don't have one either — their payment moves instead.
How do I find my exact trigger rate?
Call your lender or check your mortgage portal — many added trigger-rate displays after 2022. The quick estimate (annual payments divided by balance) gets you close, but the exact figure depends on payment frequency and compounding.
Is negative amortization dangerous?
It's expensive rather than immediately dangerous: your balance grows and the eventual repayment cost rises. The danger point is the contractual trigger point — original principal or 105% of value on insured loans — where the lender requires corrective action on their schedule instead of yours.
Should I convert to fixed if I'm near my trigger rate?
Sometimes — but it's a pricing decision, not a panic decision. Converting locks today's fixed rates and gives up the variable's smaller penalty. Compare the cost of converting against raising your payment or prepaying; a licensed advisor can run all three against your actual numbers.
Get the 5-Year Cost Comparison Worksheet
Deciding between fixed and variable — or whether to convert? Run both with YOUR numbers: payments at +1% and +2%, penalty exposure, and the three questions that settle it. We'll email you the free PDF.
The Key Takeaway
If your variable mortgage has a payment that never changes, it has a trigger rate — the point where that payment stops covering interest and your balance starts growing. Know your number, watch the gap between it and your current rate, and choose your response before the next rate move chooses it for you.
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