Why Canadian Mortgage Math Is Different
If you've used a US mortgage calculator before, the numbers here will look slightly different even at the identical rate — and that's not a bug. By law, Canadian fixed-rate mortgages compound semi-annually rather than monthly, per Section 6 of Canada's Interest Act. A lender quoting you 6% isn't quoting a rate that gets divided by 12 for a monthly rate the way it would in the US — they mean 3% every six months, which works out to a 6.09% effective annual rate before it gets converted down to a monthly figure for your actual payment. Add to that a genuinely Canadian concept most first-time buyers have never encountered — the split between amortization and term — plus mandatory default insurance below a 20% down payment, and a US-style calculator simply produces the wrong number for a Canadian mortgage, not just a slightly-off one.
How This Calculator Works
Every calculation on this page starts from the same conversion. Given a nominal annual rate quoted by your lender:
Periodic Rate (for your payment frequency) = (1 + Effective Annual Rate)1⁄periods-per-year − 1
For monthly payments, that means raising to the 1/12 power; for the bi-weekly options, 1/26; for weekly, 1/52. Once the periodic rate is set, payment amount uses the same fixed-payment annuity formula every amortizing loan uses — the compounding convention is what's uniquely Canadian, not the payment formula itself. If your down payment is under 20%, the CMHC premium (below) is calculated and added directly to the mortgage balance before that payment is computed, since that's what actually happens: you don't pay the premium separately, you finance it.
Two more things update automatically as you adjust the main fields. Entering an Annual Prepayment re-runs the amortization with that lump sum applied to principal once a year, on top of your regular payments, and reports the shorter payoff time and the interest that saves — the same mechanism behind your lender's prepayment privilege, just calculated for you instead of left to a rule of thumb. The Down Payment Scenarios table below your results recalculates the mortgage amount and payment at the standard 10%/15%/20% tiers for whatever home price and rate you've entered, so you can see the real cost of a smaller down payment (higher CMHC premium, higher payment) against a larger one without re-entering numbers three separate times.
CMHC Mortgage Insurance: What It Costs and When You Need It
Any mortgage with less than 20% down is legally required to carry mortgage default insurance — commonly called CMHC insurance after Canada Mortgage and Housing Corporation, though Sagen and Canada Guaranty also underwrite it on identical terms. Your lender picks the insurer; you don't. The premium is a percentage of your mortgage amount (not the home price), tiered by how much you're putting down:
| Down Payment | Loan-to-Value | Premium |
|---|---|---|
| 5% | 95% | 4.00% |
| 10% | 90% | 3.10% |
| 15% | 85% | 2.80% |
| 20%+ | 80% or less | Not required |
The minimum down payment itself is tiered too: 5% on the first $500,000 of the purchase price, 10% on the portion between $500,000 and $1.5 million, and a flat 20% on anything at or above $1.5 million — which is also the price ceiling above which mortgage default insurance isn't available at all, insured or not. Since December 2024 reforms, first-time buyers and buyers of newly built homes can also stretch an insured mortgage to a 30-year amortization instead of the standard 25-year cap, for a 0.20 percentage point premium surcharge — check the box on the Mortgage Payment tab above if either applies to you. One detail that catches buyers off guard at closing: several provinces (Ontario, Quebec, Manitoba, Saskatchewan) charge provincial sales tax on the CMHC premium itself, payable in cash — it can't be rolled into the mortgage the way the premium itself can.
Amortization vs. Term: The Most Confusing Part of a Canadian Mortgage
Amortization is the total time it will take to pay off your mortgage completely if nothing changes — typically 25 years, or up to 30 for eligible insured buyers. Term is something else entirely: how long your current interest rate and contract conditions are locked in before you have to renew, commonly 5 years, sometimes shorter. The two numbers are almost never the same, and that's the point — you'll renew your mortgage 4 to 6 times over a 25 to 30 year amortization, and at each renewal your rate resets to whatever's available then, whether that's higher or lower than what you're paying now. If you've only ever dealt with a US 30-year fixed mortgage, where the rate never changes for the life of the loan, this is the single biggest adjustment: a Canadian mortgage's headline rate is really only guaranteed for the current term, not the whole amortization. The "Balance at end of term" figure on the Mortgage Payment tab shows you what you'll actually owe when that renewal conversation happens.
The Mortgage Stress Test: What You'll Actually Qualify For
Every federally regulated lender in Canada — meaning all the major banks — must qualify you at a rate higher than the one you'll actually pay. This is OSFI's B-20 guideline, commonly called the mortgage stress test, and it applies to new purchases, refinances, and switches to a new lender (though not to renewing with your existing lender without increasing the loan or extending the amortization, since November 2024).
With most current rates well above 3.25%, the contract-rate-plus-2% side almost always wins in practice — the 5.25% floor mostly matters when rates are unusually low. Once the qualifying rate is set, your lender checks two ratios against your income: GDS (Gross Debt Service), your housing costs alone (stress-tested mortgage payment, property tax, heating, half of any condo fees) divided by income, capped at 39%; and TDS (Total Debt Service), the same costs plus all your other debt payments, capped at 44%. The Stress Test Affordability tab above runs both ratios and reports whichever one binds first — usually TDS if you're carrying other debt, GDS if you're debt-free — since that's the real ceiling on what you'll be approved for, independent of what you'd personally be comfortable paying.
Payment Frequency: Regular vs. Accelerated
Canadian mortgages commonly offer six payment schedules, and the distinction between the "regular" and "accelerated" versions of bi-weekly and weekly is worth understanding before you pick one. A regular bi-weekly or weekly payment is calculated so that 26 or 52 payments a year add up to the same total as 12 monthly payments — same total cost, just smaller, more frequent payments. An accelerated payment is calculated differently: it's simply half your monthly payment (bi-weekly) or a quarter of it (weekly), paid on that faster schedule. Since there are 26 bi-weekly periods in a year rather than 24 (two payments times 12 months), an accelerated bi-weekly schedule sneaks in the equivalent of one extra full monthly payment every year — applied entirely to principal, with no change to your rate. That's the entire mechanism behind the commonly-cited advice to "switch to accelerated bi-weekly to pay off your mortgage years early" — it isn't a trick, it's just a disciplined extra payment built into the schedule automatically.
What Lenders Look At Beyond the Numbers
The stress test and down payment rules are the same for every applicant at a given lender, but approval and pricing still depend on the individual file: credit score (most lenders want 680+ for the best rates, though insured mortgages can sometimes work with less), employment stability (2+ years at a job or in a field, or a longer track record if self-employed), the property itself (condos, rural properties, and unique builds sometimes face extra scrutiny or lower maximum LTVs), and existing debt beyond what shows up in TDS, like a spouse's obligations if they're not on the mortgage. A mortgage broker who can shop your file across multiple lenders — rather than a single bank only offering its own products — is often worth the conversation specifically because qualifying criteria vary more between lenders than the headline rate does.
What This Calculator Doesn't Cover
This tool calculates payment, insurance, and stress-test affordability accurately for a standard fixed-rate insured or uninsured mortgage — it doesn't replace an actual lender's underwriting or a mortgage broker's file review. Land transfer tax (which varies significantly by province and, in Toronto's case, includes an additional municipal tax on top of Ontario's provincial one) isn't part of this calculation — use our dedicated Land Transfer Tax Calculator for that, since it's a separate, one-time closing cost that can't be financed into the mortgage anyway. Variable-rate mortgages aren't legally required to compound semi-annually the way fixed-rate mortgages are — select "Variable" as the rate type and choose the compounding your specific contract uses (semi-annual is still common, but some lenders compound monthly instead) for an accurate payment either way. The Annual Prepayment field assumes your lender's prepayment privilege comfortably covers the amount you enter — actual privileges are typically capped at 10-20% of the original principal per year, so check your specific contract before counting on a larger lump sum, and this tool also doesn't model the penalty for breaking a fixed-rate term early, which can be substantial, or other closing costs like legal fees and title insurance. Treat every figure here as a solid planning estimate to bring into a conversation with an actual lender or mortgage broker, not a substitute for one.
Frequently Asked Questions
Why is my Canadian mortgage payment different from a US mortgage calculator with the same rate?
By law, Canadian fixed-rate mortgages compound semi-annually rather than monthly. A 6% Canadian mortgage actually works out to a 6.09% effective annual rate, then gets converted to a monthly rate for payment purposes — which is slightly lower than simply dividing 6% by 12 the way a US calculator would. The difference is small per payment but real over the life of the loan, and it always favors the Canadian borrower.
What's the difference between amortization and term?
Amortization is the total time to pay off the mortgage completely (typically 25 years, up to 30 for some insured buyers). Term is how long your current interest rate is locked in before you have to renew (commonly 5 years). You'll renew your mortgage 4-6 times over a 25-30 year amortization, and your rate can change at every renewal — this is the single most confusing part of a Canadian mortgage for anyone used to US 30-year fixed loans, where the rate never changes.
Do I have to pay CMHC insurance?
Only if your down payment is less than 20% of the purchase price (and the home is priced under $1.5 million, above which insured mortgages aren't available at all). The premium is added to your mortgage balance rather than paid in cash, so you finance it — and pay interest on it — over the life of the loan. Some provinces also charge sales tax on the premium itself, due in cash at closing.
What is the mortgage stress test and do I have to pass it?
Federally regulated lenders (all the major banks) must qualify you at the higher of your contract rate plus 2%, or a 5.25% floor — not the rate you'll actually pay. This is mandatory for new mortgages, refinances, and switches to a new lender, though it doesn't apply when you renew and stay with your current lender. It typically reduces the mortgage amount you qualify for by 15-25% compared to what your actual rate would suggest.
What's an accelerated bi-weekly payment and is it worth it?
An accelerated bi-weekly payment is exactly half your monthly payment, paid every two weeks — which works out to 26 half-payments a year, the equivalent of 13 full monthly payments instead of 12. That one extra payment per year, applied entirely to principal, meaningfully shortens your amortization and cuts total interest — with no change to your rate or terms, just a different payment schedule.
How much mortgage can I actually qualify for?
It's whichever is lower: what you want to borrow, or what the stress test allows based on your income, debts, and the qualifying rate (not your actual contract rate). The Stress Test Affordability tab above estimates that second number directly from your income, existing debts, and property costs, using the same 39% GDS / 44% TDS limits federally regulated lenders apply.
This calculator provides estimates for general informational purposes only and is not financial, legal, or tax advice. CMHC premium tiers, down payment rules, and the stress test qualifying rate reflect 2026 federal rules and change periodically — always confirm current figures and your specific situation with a licensed mortgage professional before signing anything.