There is a twist in Canadian law regarding mortgages. Quoting from the page linked below. --- Canada’s Interest Act states the following about amortizing mortgages: “... the principal money and the rate of interest chargeable on that money, calculated yearly or half-yearly, not in advance.” --- This page does go into the detail a little more. https://wowa.ca/how-is-mortgage-interest-calculated

It may not be authoritative but you can start with https://laws-lois.justice.gc.ca/eng/acts/i-15/page-1.html which should be.