THE CANADIAN PRESS/Jonathan Hayward

The Office of the Superintendent of Financial Institutions (OSFI) has introduced new rules on mortgage lending to take effect next year.

OSFI is setting a new minimum qualifying rate, or “stress test,” for uninsured mortgages (mortgage consumers with down payments 20% or greater than their home price).

The rules now require the minimum qualifying rate for uninsured mortgages to be the greater of the five-year benchmark rate published by the Bank of Canada (presently 4.89%) or 200 basis points above the mortgage holder’s contractual mortgage rate. “The main effect will be felt by first-time buyers,” says James Laird, co-founder of Ratehub.ca. “No matter how much money they put down as a down payment, they will have to pass the stress test.” The effect of the changes will be huge, resulting in a 20% decrease in affordability, meaning a first-time homebuyer will be able to buy 20% less house, explains Laird.

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MoneySense asked Ratehub.ca to run the numbers on two likely scenarios and find out what it would mean for a family’s bottom line. Here’s what they found:

SCENARIO 1: Bank of Canada five-year benchmark qualifying rate

In this case, the family’s mortgage rate, plus 200 basis points, is less than the Bank of Canada five-year benchmark of 4.89%.

According to Ratehub.ca’s mortgage affordability calculator, a family with an annual income of $100,000 with a 20% down payment at a five-year fixed mortgage rate of 2.83% amortized over 25 years can currently afford a home worth $726,939.

Under new rules, they need to qualify at 4.89%
They can now afford $570,970
A difference of $155,969 (less 21.45%)

SCENARIO 2: 200 basis points above contractual rate

In this case, the family’s mortgage rate, plus 200 basis points, is greater than the Bank of Canada five-year benchmark of 4.89%.

According to Ratehub.ca’s mortgage affordability calculator, a family with an annual income of $100,000 with a 20% down payment at a five-year fixed mortgage rate of 3.09% amortized over 25 years can currently afford a home worth $706,692.

Under new rules, they need to qualify at 5.09%
They can now afford $559,896
A difference of $146,796 (less 20.77%)

If a first-time homebuyer doesn’t pass the new stress test, they have three options, says Laird. “They can either put down more money on their down payment to pass the stress test, they can decide not to purchase the home, or they can add a co-signer onto the loan that has income as well,” says Laird. The stress test will be done at the time of refinancing as well, with one exception. “If on renewal you stay with your existing lender, then you don’t have to pass the stress test again,” says Laird. “However, if you change lenders at mortgage renewal time, you may have to pass the stress test but it’s not crystal clear now if this will be the case for those switching mortgage lenders.”

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So if you’re a first-time homebuyer, it may mean renting a little longer and waiting for your income to go up before you’re able to buy your first home. Alternatively, some first-time buyers will buy less—maybe a condo instead of a pricier detached home. Or, the new buyers may opt to get a co-signer to qualify under the new rules.

But whatever you do, if you’re a first-time buyer, make sure you understand what you qualify for using the new regulatory rules, and get a pre-approved mortgage before you start house-hunting. “This shouldn’t be something that shocks you partway through the home-buying process,” says Laird.

And finally, do your own research and run the numbers on your own family’s income numbers. You can use Ratehub.ca’s free online mortgage affordability calculator to calculate the impact of the mortgage stress test on your home affordability.