OFSI Mortgage Rule Changes for 2018: A Comprehensive Overview

The Office of the Superintendent of Financial Institutions (OFSI) has released its finalized B-20 Update to the mortgage industry. Below is a quick summary of the new changes that will go into effect January 2018. 1. A new minimum qualifying rate, or “stress test” for uninsured mortgages.


In recent years, there has been a growing concern about rapidly increasing house prices and high household debt levels in Canada. As a response, regulatory bodies have been implementing measures to ensure the long-term stability of the housing market and protect potential homeowners from unforeseen market fluctuations. One such body, the Office of the Superintendent of Financial Institutions (OFSI), announced significant changes to its B-20 guidelines for the mortgage industry, set to come into play at the start of 2018. Let’s delve deeper into these changes and assess their implications.

What is the B-20 Guideline?

Before delving into the specifics, it’s essential to understand what the B-20 guideline represents. Instituted by OFSI, the B-20 is a framework for prudent residential mortgage underwriting and is primarily aimed at federally-regulated financial institutions. Its primary objective is to ensure that these institutions are practicing safe and sound underwriting standards.

Key Change: The Introduction of a New “Stress Test”

The most significant of the OFSI rule changes in the updated B-20 guideline is the introduction of a new minimum qualifying rate, often referred to as the “stress test,” for uninsured mortgages.

  1. The Stress Test Explained: This test ensures that potential homeowners can afford their mortgage payments even if interest rates were to rise significantly. Essentially, prospective buyers will be tested against their ability to meet their mortgage obligations at a rate higher than the actual mortgage rate they’ll be paying.
  2. Uninsured Mortgages: Previously, only insured mortgages, those with a down payment of less than 20%, underwent such scrutiny. Now, the new rule expands this requirement to uninsured mortgages – those with a down payment of 20% or more.
  3. Calculation of the Qualifying Rate: Borrowers will be qualified at the higher of their mortgage rate plus 2% or the five-year benchmark rate published by the Bank of Canada.

Implications of the Stress Test

The introduction of the stress test for uninsured mortgages could have several repercussions:

Other Notable Changes

While the stress test has garnered much attention, it’s essential to recognize that the OFSI’s B-20 update encompasses other potential changes as well. As of the provided summary, further details on these changes were not provided, but it’s crucial for potential homeowners, real estate professionals, and financial institutions to familiarize themselves with the entire B-20 update to understand its full scope and implications.


The OFSI’s rule changes signify a cautious approach to an ever-evolving housing market landscape. While they could pose initial challenges for potential homeowners, the underlying goal is to ensure the long-term stability of Canada’s housing market and protect consumers from the pitfalls of an unpredictable interest rate environment.

For those looking to enter the housing market or refinance in 2018, it’s more important than ever to understand these changes. Seeking guidance from financial advisors or mortgage professionals can provide clarity and help in navigating this new mortgage landscape.

Remember, preparation is key. By understanding the rules and adapting to them, potential homeowners can make informed decisions that ensure both immediate satisfaction and long-term financial security.