What is the maximum mortgage amount one now qualifies for with the rules that came into effect on October 17th?

Short answer: LESS. A minimum of 20% less, in fact.

Before October 17th, the lenders calculated the maximum mortgage amount based on the contract rate of 2.49%, but now it is based on the Bank of Canada benchmark rate of 4.64%

Here are three random scenarios that I have created to outline borrowers’ qualifying power before and after the change. Note they are all based on  25-year amortization, the new qualifying interest rate (5-year Bank of Canada benchmark, currently 4.64%) as well as a GOOD credit score of 680 or greater. The first two are based on 5% down; the third is based on a 20% down payment, which does not require mortgage insurance.