# How does OSFI's B-20 guideline impact mortgage portability?

> OSFI's Guideline B-20 shapes how FRFIs assess mortgage applications, including those involving portability.

Category: Strategy
Last verified: 2026-02-18
Source: https://ratellow.com/faqs/strategy/how-does-osfis-b-20-guideline-impact-mortgage-portability

## Answer
OSFI's Guideline B-20 shapes how FRFIs assess mortgage applications, including those involving portability. It emphasizes that lenders must thoroughly evaluate a borrower's ability to manage their debts. B-20 effectively sets the standard for responsible lending practices.

## Institutional highlights
- Lenders must make sure you can comfortably afford your mortgage payments.
- Lenders will look at your overall financial situation to see if you're able to handle your debt.
- You'll need to show proof of income and a good credit history to get approved for a mortgage.
- Your lender needs to be confident in the value of the property you're buying.
- Lenders have their own rules for mortgages, based on how much risk they're willing to take.

## Related guide
- https://ratellow.com/guides/mortgage-portability-guide

## Sources
- OSFI exempts uninsured mortgage straight switches from the prescribed MQR and implements portfolio LTI limits — https://www.osfi-bsif.gc.ca/en/guidance/guidance-library/osfi-exempts-uninsured-mortgage-straight-switches-prescribed-mqr-implements-portfolio-lti-limits
- I. Purpose and scope of the guideline — https://www.osfi-bsif.gc.ca/en/guidance/guidance-library/residential-mortgage-underwriting-practices-procedures-guideline-2017#1.0
- Mortgage insurance — https://www.osfi-bsif.gc.ca/en/guidance/guidance-library/residential-mortgage-underwriting-practices-procedures-guideline-2017#2.5.1