What is the BC mortgage stress test?

It is Guideline B-20, a federal rule requiring federally regulated lenders (Canada's Big Six banks and federal credit unions) to qualify every borrower at the greater of the contract rate plus two percentage points, or 5.25%. It works the same way in BC as everywhere else, because underwriting at those lenders is federal jurisdiction; there is no provincial variant. The Canada Mortgage and Housing Corporation applies the same test to insured mortgages with less than 20% down. The qualifying rate is not what you pay each month. It is what the lender uses to decide how much it will lend, which makes it the ceiling on your purchase price.

Who is exempt from the stress test?

Only federally regulated lenders are bound by it. Provincial credit unions answer to the BC Financial Services Authority instead, and mortgage investment corporations and private lenders underwrite on their own terms; most do not run a stress test at all. Separately, since November 21, 2024 a federally regulated borrower can move an uninsured mortgage to another lender at renewal without re-passing it, provided the balance and remaining amortization are unchanged. Going outside the federal system almost always costs something: provincial credit unions typically price 25 to 75 basis points above the bank market, private lenders several hundred above. Ask any lender to put their qualifying rule in writing before assuming otherwise.

What is the difference between the qualifying rate and the contract rate?

The contract rate is what you pay: the rate on the commitment letter that sets your monthly principal and interest. The qualifying rate is what the lender tests you against, and under B-20 it is the greater of the contract rate plus two percentage points, or 5.25%. At a 5.5% contract rate you are qualified at 7.5%. At 3.0% you are qualified at 5.25%, because the floor binds. One sets the payment, the other sets the size of the loan. When an affordability calculator shows you a maximum purchase price, the useful question is which of the two it used, because the answers differ by roughly a fifth of the price.

How much does the stress test reduce my maximum mortgage?

For a borrower on a 5.5% contract rate, being qualified at 7.5% instead cuts the maximum by roughly 15 to 20%, depending on the amortization and which debt service ratio binds first. As a rule of thumb on a 25 year amortization, each percentage point of uplift costs about 9 to 10% of the maximum mortgage. A 30 year amortization, available on insured mortgages for first-time buyers and new builds since December 2024, reduces the bite a little. The affordability calculator on this site runs the test in reverse to give the actual figure for your income and down payment.

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BC Real Estate Glossary

OSFI Mortgage Stress Test (B-20)

Also known as: Stress test · B-20 · Mortgage qualifying rate

OSFI Guideline B-20 requires federally-regulated lenders to qualify mortgage borrowers at the greater of (a) the contract rate plus 2 percentage points or (b) the Bank of Canada qualifying rate (5.25%).

Guideline B-20, written by the Office of the Superintendent of Financial Institutions, requires every federally regulated lender (the Big Six banks and federal credit unions) to qualify a borrower at the greater of the contract rate plus two percentage points, or 5.25%. The Canada Mortgage and Housing Corporation applies the same higher-of test to insured mortgages with less than 20% down. It is not a rate anyone pays. It is the rate the lender puts into the gross and total debt service ratios to size the largest mortgage it will write, while the contract rate sets the actual monthly payment.

Provincial credit unions, mortgage investment corporations and private lenders sit outside it. Provincial credit unions answer to the BC Financial Services Authority rather than the federal regulator, and private lenders underwrite on their own terms. That is a real route for a buyer whose bank approval lands them short of the submarket they want, with a real cost attached: provincial credit unions typically price 25 to 75 basis points above the bank market, and private lenders several hundred above.

Since November 21, 2024, an uninsured borrower can move a mortgage to a different federally regulated lender at renewal without passing the test again, provided the balance does not rise and the amortization is not extended. Insured borrowers have had that since January 2024. Renewing with the existing lender never triggered it, because a renewal is not a new loan. A refinance still does. The effect is that an incumbent lender no longer knows you have nowhere to go.

The size of the gap surprises people. At a 5.5% contract rate you qualify at 7.5%; at 3.0% you qualify at 5.25%, where the floor binds. Roughly, each percentage point of uplift takes 9 to 10% off the maximum mortgage on a 25 year amortization, so a typical approval lands 15 to 20% below what the contract rate alone suggests. Thirty year amortizations, available on insured mortgages for first-time buyers and new builds since December 2024, soften it slightly.

One timing detail is worth knowing before you write an offer. The qualifying rate is calculated at funding, not at application. A borrower who holds a rate in week one and funds in week ten is tested against the funding-day number. If rates have moved up in between, the maximum mortgage can move down between the rate hold and the closing. Reconfirm the math the week before subject removal if the approval is anywhere near the edge.

Two tools here answer two different questions. The affordability calculator inverts this test, applying the debt service ceilings at the qualifying rate to work back to a maximum purchase price. The mortgage calculator computes the monthly payment at the contract rate. If any affordability tool gives a number that feels generous, the question to ask is which of the two rates it used. For the rule text and its citations, see /codex#osfi.b20.stress_test; the insurance cap is the adjacent limit that sets the rest of the federally regulated ceiling.

Frequently asked questions

What is the BC mortgage stress test?: It is Guideline B-20, a federal rule requiring federally regulated lenders (Canada's Big Six banks and federal credit unions) to qualify every borrower at the greater of the contract rate plus two percentage points, or 5.25%. It works the same way in BC as everywhere else, because underwriting at those lenders is federal jurisdiction; there is no provincial variant. The Canada Mortgage and Housing Corporation applies the same test to insured mortgages with less than 20% down. The qualifying rate is not what you pay each month. It is what the lender uses to decide how much it will lend, which makes it the ceiling on your purchase price.
Who is exempt from the stress test?: Only federally regulated lenders are bound by it. Provincial credit unions answer to the BC Financial Services Authority instead, and mortgage investment corporations and private lenders underwrite on their own terms; most do not run a stress test at all. Separately, since November 21, 2024 a federally regulated borrower can move an uninsured mortgage to another lender at renewal without re-passing it, provided the balance and remaining amortization are unchanged. Going outside the federal system almost always costs something: provincial credit unions typically price 25 to 75 basis points above the bank market, private lenders several hundred above. Ask any lender to put their qualifying rule in writing before assuming otherwise.
Does the stress test apply at mortgage renewal?: Usually not. Renewing with your existing lender never triggered it, because a renewal is not a new loan. Since November 21, 2024 you can also move an uninsured mortgage to a different federally regulated lender without re-passing it, as long as it is a straight switch: the balance does not rise and the amortization is not extended. Insured borrowers have had the same relief since January 2024. A refinance still triggers the full test, whoever the lender is, because the loan is changing size or length. The practical upshot is that you can now ask your lender for their best renewal offer, price a switch against it, and actually take the better one.
What is the difference between the qualifying rate and the contract rate?: The contract rate is what you pay: the rate on the commitment letter that sets your monthly principal and interest. The qualifying rate is what the lender tests you against, and under B-20 it is the greater of the contract rate plus two percentage points, or 5.25%. At a 5.5% contract rate you are qualified at 7.5%. At 3.0% you are qualified at 5.25%, because the floor binds. One sets the payment, the other sets the size of the loan. When an affordability calculator shows you a maximum purchase price, the useful question is which of the two it used, because the answers differ by roughly a fifth of the price.
How much does the stress test reduce my maximum mortgage?: For a borrower on a 5.5% contract rate, being qualified at 7.5% instead cuts the maximum by roughly 15 to 20%, depending on the amortization and which debt service ratio binds first. As a rule of thumb on a 25 year amortization, each percentage point of uplift costs about 9 to 10% of the maximum mortgage. A 30 year amortization, available on insured mortgages for first-time buyers and new builds since December 2024, reduces the bite a little. The affordability calculator on this site runs the test in reverse to give the actual figure for your income and down payment.

Work it out with your own numbers

Affordability and stress-test calculator

CMHC Default Insurance Cap — The maximum home purchase price eligible for CMHC default mortgage insurance — raised from $1,000,000 to $1,500,000 effective December 15, 2024.
30-Year Amortization Eligibility — Insured mortgages can be amortized over 30 years instead of 25, but only for first-time buyers and for anyone buying newly built housing.
Gross Debt Service Ratio (GDS) — The share of your gross income that housing alone takes up: the mortgage payment, property tax, heat, and half of any strata fee.
Total Debt Service Ratio (TDS) — Gross debt service widened to every debt you carry: car payments, credit cards, lines of credit and student loans on top of the housing costs.
Debt Service Coverage Ratio (DSCR) — Net operating income divided by the annual mortgage payments.

Frequently asked questions

Work it out with your own numbers

Related terms

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