Porting Your Mortgage to a New Multiplex Home: How It Works in BC

Here is a situation we see all the time. A family bought their current home six or seven years ago and locked in a mortgage rate they are quite attached to. Now they are moving to a brand new multiplex home in Greater Vancouver, often so parents or adult kids can live one unit over. And somewhere between the excitement and the paperwork, someone asks: what happens to our mortgage?

The short answer is that you may be able to take it with you. Lenders call this porting. This guide walks through what porting means, how the blended rate works when you need to borrow more, the strict time limits lenders put on the whole exercise, and the cases where paying the penalty and starting fresh is the smarter move. We will also cover the wrinkle that matters most to multiplex buyers here: pre-sale completion dates.

What porting actually means

Porting means moving your existing mortgage, with its interest rate, balance, and remaining term, from the home you are selling to the home you are buying. Ratehub's guide to porting (accessed August 2026) describes it as taking your existing mortgage, along with its current rate and terms, from one property and transferring it to another. You stay with the same lender, and the clock on your term keeps running as if nothing happened.

Why bother? Two reasons. First, if your existing rate is lower than what lenders offer today, porting lets you keep it. Second, paying out a mortgage before the end of its term usually triggers a prepayment penalty, and porting is the standard way to avoid that charge when you move.

One thing surprises almost everyone: porting is not automatic, and it is not a right. Your lender treats it as a fresh application. They will look at your income, your credit, and the home you are buying, and you have to qualify under today's lending rules, not the rules that applied when you first signed. In our experience, families assume porting is a ten-minute phone call. It is closer to a full mortgage application, so start the conversation before you list your current home, not after it sells.

The conditions attached

• Same lender. You cannot port a mortgage from one bank to a different bank. Changing lenders means breaking the mortgage and paying the penalty.
• Full re-approval. Income, credit, and debt levels all get reviewed again, under current rules.
• The new home has to pass review too. A single strata unit in a brand new multiplex is an ordinary residential purchase, so the property itself is rarely the problem, but the lender will still appraise and approve it.

There is one more catch, and it is a big one for anyone on a variable rate. Most variable-rate mortgages cannot be ported. Both Ratehub and WOWA's porting guide (accessed August 2026) note that variable mortgages typically are not portable, and WOWA points out that lenders will usually ask you to convert to a fixed rate first. If you are on a variable rate and hoping to port, call your lender this week, not later.

Port and increase: how the blended rate works

Most families moving from an older condo or townhouse into a brand new multiplex home need a bigger mortgage, not the same one. Lenders handle this with something called port and increase. Your existing balance keeps its existing rate. The new money you borrow is priced at today's rate. Then the lender blends the two into a single rate on the combined amount.

A simplified example, using a straight weighted average:

• Existing balance: $600,000 at 3.00%
• New money needed: $200,000 at a market rate of 5.00%
• Simple weighted average: ($600,000 x 3.00% + $200,000 x 5.00%) divided by $800,000 = 3.50%

Real quotes are messier than that. Lenders also weight the blend by how much time is left on your term, and many will extend everything into a fresh five-year term at the same time, an option Ratehub calls blend and extend. So treat the 3.50% above as the idea, not a promise. The actual number comes from your lender, in writing.

Our honest take: a blended rate is convenient, and convenience always has a price. Before you accept a blend, ask your lender two questions. What is the blended rate on the combined amount? And what would the same amount cost as a completely new mortgage at today's rates, after paying the penalty? Sometimes the blend wins. Sometimes it does not. You only find out by pricing both.

The timing window between selling and buying

Here is the rule that surprises people. When you port, your lender sets a deadline: the purchase of the new home must close within a set number of days of the sale of your old one. Ratehub and WOWA both put the typical range at 30 to 120 days, and both are clear that every lender sets its own number. Some are stricter than others. The only figure that matters is the one in your mortgage contract.

Miss the window and the port simply fails. Your mortgage gets paid out when your sale closes, the prepayment penalty applies, and your new home gets a brand new mortgage at whatever rates are doing that month.

So before you list your current home, get three things from your lender in writing: whether your mortgage is portable at all, the exact number of days in your window, and whether the window can ever be extended. Then hand those dates to your realtor and your lawyer or notary so the completion dates line up on purpose rather than by luck.

The pre-sale wrinkle: completion dates that move

Now for the part that is specific to buying a brand new multiplex home. Many of the homes on MultiLiving are sold pre-sale: you sign a purchase agreement now and complete when the home is finished, which can be many months away. Completion dates on pre-sale homes also move. A home expected in March can become a home delivered in June, and the contract usually allows for that.

Port windows are measured in days. Pre-sale timelines are measured in seasons. If you sell your current home in October and your new home completes the following summer, no 90-day window is going to stretch across that gap. This is the single most common reason porting does not work for pre-sale buyers, and it is far better to know it a year out than a month out.

What can you actually do about it?

• Time your sale late. Where possible, list your current home so its completion lands close to the expected completion of the new one, and leave room for the pre-sale date to slip.
• Negotiate a longer completion on your sale, or a rent-back where your buyer lets you stay on as a tenant for a short period. Not every buyer will agree, but it costs nothing to ask.
• Ask your lender, in writing, what happens to the port if the new home's completion date moves.
• Have a plan B. Know today what your penalty would be and what a fresh mortgage would look like, so that a failed port is an inconvenience rather than a crisis.

One more pre-sale note. Lender approvals and rate holds are usually much shorter than pre-sale timelines, so expect to have the mortgage conversation twice: once when you sign the purchase agreement, and again a few months before completion, when the real approval happens. That second conversation is where porting either works or does not, so book it early.

When breaking the mortgage beats porting

Porting exists to protect a good rate. If your rate is not good anymore, protecting it makes no sense. When rates today are lower than what you are paying, the better move is often to break the mortgage, pay the penalty, and set up a new mortgage at current rates for the new home.

The penalty is the whole question, so here is how it works. The Financial Consumer Agency of Canada explains that paying out your mortgage before the end of the term, including when you sell your home, normally triggers a prepayment charge. For a variable-rate mortgage the charge is usually three months of interest. For a fixed-rate mortgage it is usually the higher of three months of interest or the interest rate differential, which compares your rate against current rates for the time left on your term. The differential can be small, or it can be tens of thousands of dollars, and you will not know which until your lender runs the number.

The comparison is simple to set up, even if the numbers take a phone call to get:

• Option one: port. Your blended rate on the combined amount, with no penalty.
• Option two: break. The penalty today, plus a new mortgage at current rates from any lender you like.

Get both in writing from your lender, and in our view it is worth getting a second quote from an independent mortgage broker at the same time. Option two opens up every lender in the market, and competition has a way of improving the numbers.

Questions to ask your lender before you list

• Is my mortgage portable, and where is that written in my contract?
• Exactly how many days is my porting window, measured from which closing to which?
• I am on a variable rate. What do I have to do to make a port possible?
• If I need to borrow more, how do you calculate the blended rate, and can I see the calculation?
• Does porting keep my remaining term, or does everything reset to a new term?
• What would my prepayment penalty be if I broke the mortgage today?
• Are there administration fees for porting, and how much?
• My new home is a pre-sale and the completion date could move. How do you handle that?

What this comes down to

• Porting moves your existing rate, balance, and term to the new home, with the same lender, after a full re-approval.
• Most variable-rate mortgages cannot be ported without converting to a fixed rate first.
• Borrowing more means a blended rate that lands between your old rate and today's rate.
• Lenders typically allow 30 to 120 days between closings. Your contract holds the real number.
• Pre-sale completion timelines often outrun porting windows, so pre-sale buyers need a plan B from day one.
• If today's rates are below your existing rate, breaking and paying the penalty often beats porting. Price both options before deciding.

Frequently asked questions

What does porting a mortgage mean?

Porting means transferring your existing mortgage, including its interest rate, balance, and remaining term, from the home you are selling to the home you are buying. You stay with the same lender, and the port must be approved like a new application.

Can I port my mortgage to a pre-sale multiplex home in BC?

Sometimes, but timing is the obstacle. Lenders require the purchase to close within a set number of days of your sale, and pre-sale completion dates are often further out than any window allows. Ask your lender early and have a backup plan.

How long do I have between selling my old home and buying the new one?

It depends on the lender. Ratehub and WOWA both report typical porting windows of 30 to 120 days between closings. Your own mortgage contract states the exact number, so confirm it in writing before you list your current home.

Can I port a variable-rate mortgage?

Usually not. Most variable-rate mortgages are not portable. Lenders will generally ask you to convert to a fixed-rate mortgage first, which changes your rate. If you are on a variable rate and planning a move, raise this with your lender as early as possible.

Do I have to qualify again when I port?

Yes. Porting is treated as a fresh application. The lender reviews your income, credit, and the new property, and you must qualify under current lending rules. Approval is not guaranteed just because you already hold the mortgage with that lender.

What is a blended rate?

When you port and borrow more, the lender combines your existing rate on the old balance with today's rate on the new money, producing one rate in between. The exact blend depends on the amounts, the time left on your term, and the lender's method.

What if my new home needs a smaller mortgage?

You can usually port and reduce the balance. But paying down more than your prepayment allowance can trigger a charge on the extra amount, as the Financial Consumer Agency of Canada notes in its guidance on prepayment penalties. Ask your lender how much you can reduce without a charge.

What penalty do I pay if I break the mortgage instead?

Typically three months of interest on a variable-rate mortgage. On a fixed-rate mortgage, it is usually the greater of three months of interest or the interest rate differential, which can be much larger. Ask your lender for the exact figure before you decide anything.

Does porting cost anything?

Porting avoids the prepayment penalty, which is the big cost. Lenders may still charge administration fees, and a purchase always involves its own costs, such as appraisal and legal fees. Ask your lender for a full list of charges before committing.

Is porting worth it if rates have dropped since I got my mortgage?

Usually not. Porting protects a below-market rate. If your rate is above today's rates, you would be preserving an expensive mortgage. Run the numbers on breaking instead: the penalty may be smaller than the savings from a cheaper new mortgage.

Can the porting window be extended?

Sometimes lenders show flexibility, but nothing is guaranteed, and an extension is a favour rather than a term you can rely on. If your dates might not fit the window, ask about an extension in writing before either deal becomes final.

When should I talk to my lender about porting?

Before you list your current home, and ideally before you sign anything on the new one. You want the porting window, the blend calculation, and your penalty figure in hand while you can still plan around them.

Does the sales team at a pre-sale handle my mortgage?

No. The sales team at a presentation centre works for the seller and has no role in your financing. Your mortgage, your porting window, and your penalty are all matters between you and your lender or mortgage broker.

What happens if my pre-sale completion date moves after my old home sells?

If the delay pushes the purchase past your porting window, the port typically fails: your mortgage is paid out with a penalty and the new home needs fresh financing. This is why pre-sale buyers should price the breaking scenario before they need it.

Next step: the home itself

If you are weighing a move into a brand new multiplex home, settle the mortgage question early, and the home question too. Browse the multiplex homes currently for sale and pre-sale on our properties page, and if you would like to talk through timing, pre-sale completion dates, or which buildings suit a two-generation household, contact us. We watch this market every day, and we are happy to help you think it through.