About this calculator
Since 2018, every federally regulated lender in Canada must qualify you at a rate you will never pay. OSFI's Guideline B-20 sets the minimum qualifying rate for uninsured mortgages at the greater of your contract rate + 2 percentage points or a 5.25% floor; the federal insured-mortgage rules mirror it for buyers with less than 20% down. OSFI reviews the floor and the buffer at least annually and confirmed both unchanged in January 2026 — so at a typical 4.50% contract rate you are tested at 6.50%, and even a 3% deal would be tested at 5.25%. (The floor replaced the older floating benchmark — the Bank of Canada's published 5-year conventional rate — in June 2021.)
Passing the rate test is only half of it. Your housing costs at that qualifying payment — principal and interest, property tax, heating, and half your condo fees — must fit inside the Gross Debt Service limit, 39% of gross income for insured mortgages; adding every other monthly debt must fit inside the Total Debt Service limit of 44%. Those 39/44 ceilings are CMHC's insured maximums (restored in July 2021 after a brief tightening to 35/42) and the same figures the federal Mortgage Qualifier Tool uses; many uninsured lenders apply them by policy. Whichever ratio runs out first sets your maximum — this calculator works out which one binds you, and by how much.
Two exemptions are worth knowing. Renewing with your current lender needs no new test, and since November 21, 2024 a straight switch of an uninsured mortgage to another federally regulated lender — same balance, same amortization, no new money — is also exempt. Provincially regulated credit unions are not bound by B-20 at all, though many apply a similar test voluntarily.
How to use it
- Enter your combined gross income and the contract rate a lender has offered (or a realistic estimate).
- Set the amortization and the down payment you have saved — the down payment does not change the mortgage you qualify for, only the price it reaches.
- Fill in the housing costs honestly: estimated property tax, heating, and condo fees all consume GDS room before the mortgage payment itself.
- Add your other monthly debts — car payments, credit-card minimums (lenders use roughly 3% of the balance), student loans. These drive TDS.
- Read the maximum mortgage at the qualifying rate, which limit binds, and use the scenario table to see what a rate move would do to your approval.
The formula
The lender works backwards: the debt-service ratios cap the monthly payment you may carry at the qualifying rate, and that payment, inverted through the standard annuity formula, caps the loan. Canadian j2 compounding is used because the qualifying payment is a Canadian mortgage payment — a US-style monthly-compounding inversion would understate the maximum slightly.
Worked example
A household earning $120,000 with a $100,000 down payment, $7,200 a year of property tax, $150 a month of heating and $400 a month of car and card debts: GDS leaves $3,150 a month for principal and interest; TDS leaves $3,250 — GDS binds. At the 6.50% qualifying rate (4.50% + 2%) over 25 years, $3,150 a month supports a $470,273 mortgage — a maximum price of $570,273. Without the stress test, the same budget at 4.50% would support $569,134: the test quietly removes about $98,861 of borrowing power.
Sources: OSFI Guideline B-20 (qualifying rate and the 5.25% floor, confirmed unchanged January 2026) and CMHC insured-lending GDS/TDS limits of 39%/44%. Last updated: October 2026.
Frequently asked questions
What is the current stress test rate in Canada?
The greater of your contract rate + 2 percentage points or 5.25%. The 5.25% is a floor set by OSFI (and mirrored in the federal insured-mortgage rules), reviewed at least annually and confirmed unchanged in January 2026. At most contract rates available today, contract + 2% is the higher figure, so the floor only bites on unusually cheap deals.
What are GDS and TDS, and what are the limits?
Gross Debt Service (GDS) is your housing costs — mortgage payment at the qualifying rate, property tax, heating, 50% of condo fees — divided by gross income. Total Debt Service (TDS) adds all other monthly debt payments. The limits most lenders apply are 39% GDS and 44% TDS, which are CMHC's maximums for insured mortgages and the federal qualifier's figures. Older articles quoting 35%/42% describe a temporary 2020–21 CMHC tightening that was reversed in July 2021.
Does the stress test apply when I renew or switch lenders?
Not if you renew with your current lender, and — since November 21, 2024 — not for a straight switch of an uninsured mortgage to another federally regulated lender when neither the balance nor the amortization increases. Add money, extend the amortization or refinance, and you qualify under B-20 again. Credit unions regulated provincially are outside B-20 entirely.
How can I qualify for more?
The levers, in rough order of power: pay off monthly debts (every $100 a month of debt payments costs roughly $15,000–$18,000 of mortgage at the qualifying rate), raise the down payment only to reach a price (it does not raise the loan itself), choose a 30-year amortization if you are an eligible first-time buyer or new-build purchaser (a smaller payment per dollar borrowed), or add a co-borrower's income. Shopping for a lower contract rate helps twice — the payment falls and so does the qualifying rate.
Why does the calculator use my debts against TDS but not GDS?
That is how the ratios are defined: GDS counts only shelter costs, TDS counts shelter plus everything else. It is also why the same debt can be harmless in a cheap house (GDS binds first) and fatal in an expensive one. The results show the payment room under each ratio separately so you can see which definition is costing you.
What formula does this canada mortgage stress test calculator use?
Qualifying rate = max(contract rate + 2%, 5.25%). Monthly P&I budget = min( (income ÷ 12 × GDS%) − tax ÷ 12 − heat − ½ condo fees, (income ÷ 12 × TDS%) − tax ÷ 12 − heat − ½ condo fees − other debts ). Max loan = budget × (1 − (1 + j2)^−n) ÷ j2, with j2 the semi-annual-compounding monthly rate and n the months in the amortization. The lender works backwards: the debt-service ratios cap the monthly payment you may carry at the qualifying rate, and that payment, inverted through the standard annuity formula, caps the loan. Canadian j2 compounding is used because the qualifying payment is a Canadian mortgage payment — a US-style monthly-compounding inversion would understate the maximum slightly. The worked example on this page applies the formula step by step with real numbers, so you can verify the result by hand.