Mortgage portability is a feature that allows you to transfer your existing mortgage, including its interest rate, remaining term, and balance, from your current property to a new one when you move. It lets you avoid breaking your mortgage contract mid-term and potentially paying thousands of dollars in prepayment penalties.
Not every mortgage can be ported. Most fixed-rate closed mortgages are portable, but variable-rate mortgages are rarely eligible. Even some fixed-rate products cannot be ported. These are commonly known as 'restricted' mortgages, which offer lower rates but sacrifice features like portability. Your mortgage agreement will confirm whether portability is available, or you can ask your lender or broker directly.
Lenders impose a time limit to complete the port. You typically have 30 to 120 days between selling your current home and purchasing your new one, though the exact window varies by lender. If your transactions do not align within the porting window, you will lose your rate and need to qualify for a new mortgage at current rates.
Even though you are keeping your existing mortgage, you must reapply and meet the lender's qualification requirements, including income, credit, and debt ratios, just as you did originally. The new home will also need to be appraised and approved by the lender. Your debt service ratios will be calculated using current stress test rates, which in 2026 means qualifying at your contract rate plus 2% or 5.25%, whichever is higher.
If your new home costs more than your remaining mortgage balance, your lender will typically offer what is called a 'blend and extend.' This is essentially a weighted average of the existing mortgage at its original rate combined with the new funds required at a current market rate. The result is a blended rate that falls somewhere between the two. If you are instead downsizing to a less expensive property, you can usually still port, but the lender may charge a partial prepayment penalty on the difference between your old balance and the reduced amount.
Porting tends to make the most financial sense when your existing rate is significantly lower than current market rates and you have substantial time remaining on your term. If the rate you can qualify for today is lower than what you currently hold, it may not make sense to port. In that case, refinancing could be the better option. Speaking with a mortgage broker before listing your home is the best way to run the numbers and determine whether porting or breaking is the right move.