DERRICK Guides · 5 min read
The Mortgage Stress Test, Explained
Why you qualify at a higher rate than you'll pay: Canada's minimum qualifying rate, who it applies to, and what it does to your budget.
Reviewed 2026-06-09 — regulatory figures are date-stamped in the text.
If a lender offers you a mortgage at 5.0%, you don’t qualify at 5.0%. You qualify as if the rate were 7.0%. That’s the stress test, and it’s the single biggest reason buyers’ budgets come in lower than expected.
The rule
As of June 2026, federally regulated lenders must qualify you at the minimum qualifying rate (MQR): the greater of your contract rate + 2%, or 5.25%. It applies to both insured mortgages (less than 20% down) and uninsured ones at banks. The logic is simple: prove you could still pay if rates rose two points, and the system doesn’t produce a wave of defaults every rate cycle.
What it does to your budget
The qualifying rate feeds into two affordability ratios lenders enforce (figures for insured mortgages):
- GDS (gross debt service): housing costs — stressed mortgage payment, property tax, heat, half of condo fees — can’t exceed 39% of gross income.
- TDS (total debt service): housing plus all other debt payments can’t exceed 44%.
Worked example: at a 5.0% contract rate over 25 years, each $100,000 of mortgage costs about $582/month — but at the 7.0% qualifying rate, the test sees about $700/month. Qualifying two points above contract cuts most buyers’ maximum mortgage by roughly 15–20% compared to the naive estimate.
A Canadian quirk worth knowing
Canadian fixed-rate mortgages compound semi-annually, not monthly. A “5%” Canadian mortgage is genuinely cheaper than a 5% U.S.-style monthly-compounded one. Every calculator on this site uses the correct semi-annual math — generic online calculators frequently don’t, and overstate your payment.
What you can do about it
- Test your real number first. Our affordability calculator applies the MQR, GDS, and TDS rules exactly.
- Pay down consumer debt before house-hunting — every $400/month car payment removes roughly $75,000 of mortgage room under TDS.
- Compare payment frequencies with the mortgage calculator; accelerated bi-weekly payments shave years off an amortization without changing qualification.
Get a second pair of eyes
A pre-approval letter is a starting point, not a guarantee. If you want yours sanity-checked against what lenders actually enforce, get in touch — it costs nothing to ask.