Port Your Mortgage vs. Break and Restart: The Math Every Moving Homeowner Needs

Published May 3, 2026

Most Canadian mortgages are portable, but the conditions and blend calculations are complex enough that many borrowers leave thousands on the table when they move. If you're planning to relocate, understanding whether to port your mortgage Canada, break it, or restart can save you significant money.

Understanding Mortgage Portability

Mortgage portability is a feature that allows you to transfer your existing mortgage to a new property without paying penalties. This can be particularly beneficial if you have a low interest rate and plan to move before your term ends.

When to Consider Porting Your Mortgage

Porting your mortgage makes sense in several scenarios:

  • You have a low interest rate that is lower than current market rates.
  • You plan to move within the same lender's service area and they offer portability options.
  • You want to avoid prepayment penalties associated with breaking your mortgage.

The Porting Process

The process of transferring a mortgage involves several steps:

  1. Contact your lender to discuss portability options and any associated fees.
  2. Apply for the new mortgage on your new property, ensuring it meets the lender's criteria.
  3. Complete the necessary paperwork and legal documentation.
  4. Close the deal on your new property and transfer the existing mortgage terms to the new home.

Blend and Extend: What You Need to Know

When you port your mortgage, you might need additional funds if your new home is more expensive. In such cases, lenders often offer a "blend and extend" option:

  • The existing mortgage balance at the original rate.
  • A new mortgage amount at the current market rate.

This blended rate can be calculated using the following formula:

Existing Mortgage BalanceNew Mortgage AmountBlended Rate Calculation
$300,000 at 3.5%$100,000 at 4.25%(300,000 * 3.5% + 100,000 * 4.25%) / (300,000 + 100,000) = 3.78%

Breaking Your Mortgage

If porting your mortgage isn't an option or doesn't make financial sense, you might consider breaking it. Breaking a mortgage involves paying penalties, such as Interest Rate Differential, to exit the current term early and restarting with a new lender.

When to Break Your Mortgage

Breaking your mortgage can be advantageous in certain situations:

  • You find a significantly lower interest rate with another lender.
  • Your financial situation has changed, and you need more flexible terms.
  • You are moving out of the lender's service area or they do not offer portability options.

Calculating Break Fees

The cost of breaking a mortgage can be substantial. Penalties typically include:

  • Interest Rate Differential (IRD): The difference between your current rate and the new rate, multiplied by the remaining amortization period.
  • Prepayment Penalty: A fixed fee or a percentage of the outstanding balance.

Tip: Always calculate the break fees using your lender's specific formula. Some lenders use the posted rate, while others use the discounted rate you actually pay.

Bottom Line: Key Takeaways

When deciding whether to port your mortgage Canada or break and restart, consider the following:

  • Evaluate current interest rates compared to your existing rate.
  • Calculate potential penalties for breaking your mortgage.
  • Consider the blended rate if you need additional funds.
  • Consult with a mortgage broker to explore all options and make an informed decision.

By understanding the nuances of mortgage portability, transfer mortgage Canada, and break mortgage moving strategies, you can save thousands when relocating. Don't leave money on the table—make sure to do your homework or consult with a professional before making any decisions.

Reviewed for accuracy
Manbir Natt BCFSA Lic. #MB612411
Licensed mortgage broker · MBA, Rotman School of Management, University of Toronto

AI-generated content. This article was produced with AI assistance and reviewed for general accuracy. It is for informational purposes only and does not constitute financial, mortgage, or legal advice. Always consult a licensed mortgage professional before making any financial decisions.

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