Share article
Share article
Summary: Porting a mortgage means moving your existing rate, balance, and remaining term from your current home to your next one when you sell and buy in close succession. Most fixed-rate mortgages from Canadian lenders are portable; most variable-rate and collateral-charge mortgages are not. Lenders typically allow 30 to 120 days between the sale and purchase closings, and the new property still has to clear underwriting at today's debt-service rules.
What does it mean to port a mortgage?
Porting a mortgage means transferring your rate, balance, and remaining term to a new home when you sell and buy. The mortgage does not literally move; your lender discharges the existing mortgage on the sale and registers a new one on the purchase at the same rate and term.
The reason porting matters is rate preservation. When current market rates are higher than the rate you locked in earlier, breaking the contract and signing a fresh mortgage at today's rate can cost thousands of dollars more in interest each year. A port avoids both the prepayment penalty and the higher new rate.
Which mortgages can be ported?
Whether your mortgage is portable depends on the product type and the lender's specific terms, both of which are set out in your mortgage commitment letter.
Fixed-rate mortgages: Almost universally portable across Canadian lenders. This is the most common case.
Variable-rate mortgages: Most lenders either do not allow porting on variable products, or attach conditions that make it impractical.
Collateral-charge mortgages: Used by some lenders in place of standard charges and typically not portable.
Default-insured mortgages: Mortgages insured through Canada Mortgage and Housing Corporation (CMHC), Sagen, or Canada Guaranty can usually have the insurance ported as well, with no new premium, as long as the new loan amount does not exceed the original insured value.
You still need to re-qualify on the new property. The lender reassesses your debt service ratios, confirms your credit score (typically 650 or higher), and underwrites the new purchase from scratch. Porting does not skip underwriting.
For a closer look at the underlying product types, see Ownright's guide to fixed vs. variable rate mortgages.
What happens if your new home costs more or less?
The arithmetic of a port depends on whether your new mortgage will be larger, smaller, or about the same size as your existing balance. The table below shows how the rate, term, and any penalties shift in each scenario.
| Same or larger mortgage | Smaller mortgage (downsizing) |
Your existing balance | Carries over at the original rate and term | Reduced; the excess is paid off |
Top-up portion | Funded at today's market rate | Not applicable |
Effective rate | Blended weighted average (blend-and-extend) | Original rate on the remaining balance |
Term reset | Often reset to a new 3- or 5-year term | Original term continues |
Prepayment penalty | None on the existing balance | Partial penalty may apply on the portion paid off |
When the new home requires more financing, the lender adds the extra borrowing at the current market rate and blends it with your existing rate to produce a single weighted average rate, usually with a fresh term. When the new home requires less, you may face a partial prepayment penalty on the portion of the original balance you no longer need. For fixed-rate mortgages, that penalty is the greater of three months of interest or the Interest Rate Differential (IRD), which can be substantial on larger balances.
How long do you have to complete a port?
Canadian lenders typically allow 30 to 120 days between your sale closing and your purchase closing for the port to qualify. The exact window is set out in your mortgage agreement and varies by lender.
If the closings line up on the same day, the port is straightforward. If they do not, two situations come up most often:
Sale closes first, purchase closes later. Your existing mortgage is discharged on the sale. The new mortgage is then registered on the purchase within your lender's porting window, at the original rate.
Purchase closes first, sale closes later. You will likely need bridge financing, a short-term loan secured against the equity in your unsold home, to fund the new purchase until your sale completes. Bridge financing carries its own setup fee and a rate typically above prime.
Coordinating these dates is part of what your real estate lawyer manages on a same-day or near-same-day buy-and-sell. The closing day walk-through explains how the lawyer, lender, and agent stay synchronized so funds arrive in the right order.
You can read the National Housing Act, R.S.C. 1985, c. N-11, which governs CMHC's mortgage insurance program, in full at laws-lois.justice.gc.ca.
When does porting actually make sense?
Porting is most worthwhile when your existing rate is meaningfully below current market rates and you are moving to a comparably priced or larger home. The blended rate stays lower than a fully new mortgage at today's rates, and you avoid the penalty for breaking the contract.
Porting is less worthwhile when your remaining term is short, when the new top-up is large enough to dilute the rate benefit, or when the prepayment penalty for breaking the mortgage would actually cost less than the port arithmetic. Running the numbers with your mortgage broker before committing to either path is the right call.
At Ownright, we focus entirely on Ontario residential real estate law. We help homeowners with purchase closings, refinances, sales, and same-day buy-and-sell transactions where a mortgage is being ported. You can start your closing online or get in touch with any questions.
Frequently asked questions
Can you port a mortgage to a property in a different province?
It depends on the lender. Most major Canadian banks allow porting between provinces, but a few smaller lenders limit porting to the same province. Check your mortgage commitment letter before assuming a cross-province move qualifies.
Does porting a mortgage trigger a credit check?
Yes. Even though you are keeping the same rate and term, the lender treats the new property as a fresh underwriting decision. They pull your credit, recalculate your debt service ratios, and confirm the new property meets their lending criteria.
How much does it cost to port a mortgage?
Most lenders do not charge a dedicated porting fee, but standard new-mortgage costs still apply: appraisal on the new property (typically $300 to $500), legal fees on the new closing, and any blend-rate calculation on a top-up. The savings come from avoiding the prepayment penalty on the original balance.
What if my new home closes before my old one sells?
You will likely need bridge financing to cover the purchase until the sale completes. Lenders typically offer bridge loans for 30 to 120 days at a rate above prime plus a setup fee. Your mortgage broker can arrange this alongside the port.
Can I port my mortgage if I'm downsizing?
Yes, but you may owe a partial prepayment penalty on the portion of your existing balance you no longer need. For fixed-rate mortgages, the penalty is the greater of three months of interest or the IRD on the prepaid amount.
Do I need a lawyer for a ported mortgage closing?
Yes. The legal side of a ported mortgage closing is the same as any other Ontario purchase: your real estate lawyer registers the new mortgage on title, reviews lender instructions, and coordinates the flow of funds. The added complexity is timing between the sale and purchase closings.
About the author
Joel Fox is a co-founder and COO at Ownright. He helps run the firm's day-to-day work on Ontario residential closings, refinances, and sales, and writes regularly to demystify the parts of a transaction that most homeowners only encounter once or twice in their lives.
Legal references: Mortgage default insurance in Canada is administered by Canada Mortgage and Housing Corporation under the National Housing Act, R.S.C. 1985, c. N-11. Mortgage charges in Ontario are registered under the Land Titles Act, R.S.O. 1990, c. L.5 and governed by the Mortgages Act, R.S.O. 1990, c. M.40.
Important note: This article is not legal advice. No one should act, or refrain from acting, based solely on the information in this post or any linked materials without first seeking appropriate legal or professional advice.
