How to use this
Start with your best guess at each input, then move them one at a time. The total monthly number updates as you type. Switch to "Payment to price" mode if you want to solve the other direction: give it a monthly ceiling and it tells you the maximum purchase price that fits.
- Purchase price. The listing or agreed price. The calculator applies the CMHC rule: under $1.5M you can put 5% down on the first $500K and 10% on the portion above; at $1.5M and up, minimum is 20%.
- Down payment. Enter either the dollar amount or the percent; they track each other.
- Interest rate. The annual nominal rate your lender quoted. Canadian mortgages compound semi-annually by law; the monthly payment conversion is baked in.
- Amortization. 25 years is standard; 30 years is available if your down is 20% or more. Longer amortization lowers payment, raises total interest.
- Frequency. "Accelerated biweekly" pays about half a month's extra per year, shaving roughly 3 years off a 25-year amortization.
Why the stress test matters
The B-20 rule requires federally regulated lenders to qualify you at the greater of your contract rate plus 2% or the published qualifying rate (5.25% as of 2026). The calculator shows both your real payment and the qualifying payment so you can see the gap. If you can afford the real payment but not the qualifying payment, you will clear the mortgage but may have to adjust your price ceiling.
Common questions
Why is the monthly rate not just the annual rate divided by twelve?
Canadian mortgage law requires semi-annual compounding, not monthly. A 5% nominal rate compounded semi-annually equals an effective annual rate of roughly 5.0625%, and the monthly rate is the 12th root of that (roughly 0.41%). Dividing 5% by 12 would overstate the rate slightly and your monthly payment would be higher than reality.
Does this calculator account for CMHC insurance?
Yes. If your down payment is under 20% the premium is added to the mortgage principal and amortized over the term. Rates follow the 2026 CMHC schedule (0.60% to 4.00% depending on loan-to-value). Down payments of 20% or more skip the premium entirely.
How accurate is the property-tax estimate?
It uses Calgary's 2026 residential mill rate applied to the purchase price. Actual assessed values diverge from sale prices, especially after a recent purchase when the assessment catches up 12-24 months later. Treat the number as a reasonable budget, not a bill.
What does the stress-test number represent?
It is what your monthly payment would be at the qualifying rate (your contract rate plus 2%, or 5.25%, whichever is higher). You do not actually pay this; it is the number the lender uses to decide whether to approve you.
Can I use this calculator for a rental property?
The math is the same, but CMHC insurance is not available on non-owner-occupied properties and minimum down is 20%. Rental property mortgages also typically carry a slightly higher rate than owner-occupied; enter that higher rate if you are modelling a rental.
What closing costs should I budget beyond what the calculator shows?
The calculator shows Alberta Land Titles fees. On top of those, budget $1,500 to $2,500 for a real estate lawyer, $250 to $400 for title insurance, $750 to $1,200 for a real property report with municipal compliance (the seller's responsibility but sometimes split), a property-tax adjustment paid to the seller for the unused portion of the year, and moving costs. A safe rule of thumb is 1.5% to 2% of purchase price for closing.
Is my data saved when I use this calculator?
No. The calculator runs entirely in your browser; nothing is sent anywhere unless you choose to email yourself the calculation using the form above.