CMHC Mortgage Portability and Blend & Extend: Keep Your Low Rate When You Move

# CMHC Mortgage Portability and Blend & Extend: Keep Your Low Rate When You Move

Moving to a new home mid-term on your mortgage used to mean one thing: breaking your mortgage and paying a hefty penalty. For borrowers who locked in at historically low rates, that penalty can easily reach $10,000 to $20,000 or more. But there are two strategies that can help you keep your existing rate or minimize the cost: mortgage portability and blend & extend.

At The Mortgage World, we help clients navigate these options every day. Understanding how they work could save you tens of thousands of dollars when you sell one home and buy another.

The Cost of Breaking a Mortgage

Before exploring the solutions, it helps to understand the problem. When you break a fixed-rate mortgage before the end of your term, your lender charges a prepayment penalty. For fixed-rate mortgages, this penalty is typically the greater of three months' interest or the Interest Rate Differential (IRD).

The IRD is calculated based on the difference between your contract rate and the rate the lender could charge for the time remaining on your term. When you locked in at a low rate and current rates are also low (or the lender uses posted rates in the calculation), the IRD can be surprisingly large.

Example penalty calculation:

Source: FCAC, Prepayment Penalties Disclosure Requirements, 2024

A $19,200 penalty is a significant cost that erodes the equity you have built. This is the scenario that portability and blend & extend are designed to avoid.

If you are approaching mortgage renewal, timing your move to coincide with the end of your term eliminates the penalty entirely. But life does not always cooperate with mortgage schedules.

How Mortgage Portability Works

Mortgage portability allows you to transfer your existing mortgage, including its current rate, remaining term, and balance, from your old property to your new one. You are essentially picking up the mortgage and carrying it to a different address.

How it works in practice:

1. You sell your current home and purchase a new one
2. You notify your lender that you want to port (transfer) your mortgage
3. The lender re-qualifies you for the new property (income, credit, property appraisal)
4. Your existing mortgage terms transfer to the new property
5. If the new home costs more, you take additional financing at current rates for the difference

Key requirements for portability:

• Your current lender must offer portability (not all do)
• You must qualify for the mortgage on the new property under current underwriting rules, including the stress test
• The sale and purchase must typically occur within 30 to 120 days of each other (timing window varies by lender)
• The new property must meet the lender's criteria (location, type, condition)

Source: OSFI, Guideline B-20, Residential Mortgage Underwriting Practices, 2023

What happens if you need a larger mortgage for the new property?

Most lenders allow you to "port and increase." Your existing balance stays at the old rate and term, and the additional amount is financed at current market rates. You effectively have two components blended together, which leads us to the next strategy.

How Blend & Extend Works

Blend & extend is a strategy where your lender combines your existing mortgage rate with current market rates and extends your mortgage to a new term. Instead of breaking the mortgage and paying a penalty, you negotiate a blended rate that falls somewhere between your old rate and today's rate.

How the blended rate is calculated:

The lender weights the old rate and the new rate based on the remaining balance, additional funds needed, and time remaining on the original term versus the new term.

Simplified example:

In this example, the borrower avoids a penalty entirely and locks in a blended rate of approximately 3.56%, which is significantly lower than taking a new mortgage at the full current rate of 4.89%.

The exact calculation varies by lender. Some lenders use a simple weighted average, while others apply more complex formulas that account for the time remaining on the original term. Your broker can request the exact blended rate from the lender before you commit.

Portability vs Blend & Extend: When to Use Each

Both strategies can save you money, but they work differently and are suited to different situations.

If you are currently on a variable-rate mortgage, breaking the mortgage is often the simpler and cheaper option, since the penalty is capped at three months' interest. Portability and blend & extend provide the greatest value for fixed-rate borrowers with significant rate differentials.

Lender Differences You Need to Know

Not all lenders offer portability or blend & extend, and the terms vary significantly among those that do.

Portability availability:

• Most major banks (RBC, TD, BMO, Scotiabank, CIBC) offer portability on fixed-rate mortgages
• Credit unions vary widely in their portability offerings
• Monoline lenders (those that only do mortgages) often offer portability with competitive terms
• Some lenders restrict portability to specific mortgage products or require minimum balances

Timing windows:

The gap between selling your old home and closing on the new one is critical. Each lender sets its own portability window:

If your sale and purchase dates fall outside the lender's window, you lose the ability to port and will face the prepayment penalty. This is one of the most common reasons portability falls through, and why coordinating your sale and purchase timelines is essential.

Source: FCAC, Understanding Your Mortgage Agreement, 2024

At The Mortgage World, we help clients evaluate their current lender's portability terms before they list their home for sale. Knowing the rules in advance allows you to structure the transaction timeline accordingly.

Planning Your Move: A Step-by-Step Approach

If you are considering a move and want to preserve your existing mortgage rate, follow these steps:

Step 1: Review your mortgage agreement. Check whether your mortgage includes a portability clause. If you are unsure, your broker can review the terms with you.

Step 2: Calculate the potential penalty. Even if you plan to port, know what the penalty would be as a fallback. This gives you a baseline for comparing strategies. Our guide to mortgage refinancing covers how penalties are calculated in more detail.

Step 3: Assess the timing. Determine whether you can realistically close both the sale and the purchase within your lender's portability window. In hot markets, this is often feasible. In slower markets, the gap may be too wide.

Step 4: Get pre-approved for the port. Your lender will need to re-qualify you under current rules. A pre-approval for the ported mortgage ensures there are no surprises. If you also need additional funds, the lender will quote a blended rate at this stage.

Step 5: Coordinate with your broker. Your broker can negotiate the blend & extend rate, confirm the portability timeline, and compare the total cost against simply breaking the mortgage and starting fresh with a new lender.

When Breaking the Mortgage Is Actually the Better Choice

Portability and blend & extend are not always the right answer. There are situations where paying the penalty and starting fresh makes more financial sense.

Consider breaking the mortgage when:

• The penalty is small (variable rate or near the end of your term)
• A different lender is offering a significantly lower rate that offsets the penalty cost
• Your current lender's portability terms are restrictive
• You want to change your amortisation, switch between fixed and variable, or access equity through a refinance
• The timing window does not work for your sale and purchase dates

A good broker will run the numbers on all scenarios and present you with a clear comparison. The best strategy depends on your specific rate, balance, time remaining, and the current rate environment. If you are also considering accessing equity, read our comparison of refinancing versus a HELOC for additional context.

Let The Mortgage World Help You Keep Your Rate

Whether you are porting your mortgage, negotiating a blend & extend, or weighing the cost of breaking your mortgage entirely, the numbers matter. The difference between the right strategy and the wrong one can easily be $10,000 to $20,000.

At The Mortgage World, we analyse your existing mortgage terms, calculate every option, and present a clear recommendation. If you are thinking about moving before your term is up, contact us before you list your home. Early planning gives you the most options and the best outcome.

References

• FCAC, Prepayment Penalties: https://www.canada.ca/en/financial-consumer-agency/services/mortgages/prepayment-penalties.html
• OSFI, Guideline B-20, Residential Mortgage Underwriting Practices: https://www.osfi-bsif.gc.ca/en/guidance/guidance-library/residential-mortgage-underwriting-practices-and-procedures
• FCAC, Understanding Your Mortgage Agreement: https://www.canada.ca/en/financial-consumer-agency/services/mortgages/understanding-mortgage-agreement.html