Canadian Mortgage Stress Test Calculator (2026)

OSFI Guideline B-20 requires federally-regulated lenders to qualify mortgage applicants at a higher rate than their contract rate, to ensure the borrower could still service the mortgage if rates rise. The qualifying rate is the GREATER of (a) the contract rate plus 2 percentage points, or (b) the 5.25% Minimum Qualifying Rate (MQR) floor. The borrower's debt-service ratios are then computed at that qualifying rate.

GDS (Gross Debt Service) is the percentage of monthly gross income consumed by housing costs: mortgage payment at the qualifying rate, property tax, heating, plus 50% of condo fees if applicable. TDS (Total Debt Service) adds all other monthly debt payments (car loans, student loans, credit card minimums) on top of GDS. OSFI B-20 caps GDS at 39% and TDS at 44% for insured high-ratio mortgages.

Per OSFI B-20 convention, half of monthly condo fees are treated as housing-cost equivalent for the purposes of GDS calculation, since condo fees include items that would otherwise be borne directly by the homeowner (e.g. insurance, building maintenance, some utilities).

It applies to new originations and refinances at federally-regulated lenders, both insured (high-ratio) and uninsured. There are two notable exemptions for renewal switches. First, OSFI's letter of September 24, 2024 (effective November 21, 2024) waived the Minimum Qualifying Rate for uninsured straight switches at renewal — a borrower with at least 20% equity moving an existing mortgage to a new federally-regulated lender at the same amortization can now qualify at the contract rate. Second, the insurer-side rule has long exempted insured renewal switches from re-qualification when the loan amount and amortization stay the same. The calculator above includes a 'Renewal switch' toggle that applies the OSFI uninsured exemption when down payment is at least 20%. Provincially-regulated lenders (some credit unions) are outside OSFI's scope and may apply their own rules.

The 5.25% floor binds. If your contract rate is, say, 3.99%, contract + 2% = 5.99%, which is above the 5.25% floor — so 5.99% becomes the qualifying rate. If your contract rate is 3.00%, contract + 2% = 5.00%, which is below the 5.25% floor — so 5.25% becomes the qualifying rate. The floor exists to prevent the qualifying rate from becoming too low even when contract rates fall sharply.

The lender will not approve the mortgage at the requested principal. Options the borrower could explore (informational, not advice): increase the down payment, reduce the home price target, lengthen the amortization (within the 25/30y limits per the Dec 2024 reforms), pay down other debts to reduce TDS, or apply with a co-signer. Some provincially-regulated credit unions apply less strict rules, but the federally-regulated lender market is the bulk of the Canadian mortgage market.

No — this calculator computes the stress test based on the loan principal you enter (home price minus down payment). If your down payment is under 20%, CMHC insurance is required and adds 0.6%–4% to the loan principal. Run the CMHC Insurance calculator first to compute the premium, then add it to the home-price-minus-down-payment value before running the stress test for the most accurate result.