I'm on a cheap fixed rate. Do I lose it if I sell?

This is one of the most common reasons people talk themselves out of moving, and it is usually based on a fear rather than a fact. The rate you fixed in a cheaper year is not automatically lost the day you accept an offer.

What does porting a mortgage actually mean?

Porting a mortgage is transferring your existing mortgage deal from the home you are selling to the home you are buying, keeping the same lender, the same interest rate and the same remaining term. The loan is not paid off and replaced. It moves across with you.

Because the deal survives the move, an early repayment charge is normally avoided. An early repayment charge is the fee a lender applies when you exit a fixed deal before it ends, and it is commonly set at 1% to 5% of the outstanding balance depending on how many years of the fix remain.

Why does this matter so much in 2026?

Because the gap between old fixes and new ones is still wide. As of 9 September 2026 the Bank of England base rate stood at 3.75%, with average rates of 5.29% on a two-year fix and 5.31% on a five-year fix at 75% loan to value, against a standard variable rate averaging 7.34%.

UK Finance's forecast has around 1.8 million fixed-rate deals ending during 2026. If yours was agreed in the low-rate years, the deal itself is now one of the more valuable things you own, and it is worth knowing whether it can travel with you.

Those figures are an illustration on a single loan size, not a quote. The point they make is that the deal you are sitting on can be worth more than the few thousand pounds people usually argue about at the offer stage.

Is porting guaranteed?

No. This is the part that catches people out, and it is worth understanding before you list rather than after you have accepted an offer.

Porting requires a new application to your existing lender. They reassess your income, employment and credit record against their current lending rules, and they assess the property you are buying.

What should I do before I put my house on the market?

1. Find your mortgage offer document and check two things: whether the product is portable, and the exact early repayment charge and the date it steps down or ends.
2. Call your lender and ask for a porting illustration based on a realistic purchase price. This is a normal request and does not commit you to anything.
3. Ask what they would lend you today, not what they lent you originally.
4. If you need extra borrowing, ask what rate the second part would be on and whether the end dates can be aligned.
5. Speak to a mortgage broker as well, because in some cases a new deal elsewhere beats keeping the old one once the second part is priced in.

A cheap fixed rate is worth protecting. It is not worth being trapped by.

When is it better to let the fix go?

Sometimes the arithmetic points the other way. If your fix has only a few months left, the early repayment charge may be small enough to ignore. If you are borrowing a lot more, the blended cost of a low ported part and a large expensive second part can end up higher than one new deal on the whole amount.

Work it out on the total monthly cost of both options over the same period, including any product fees, rather than comparing the two headline rates. The rate on your old part is only doing work on the balance it covers.

How does this change what I do about selling?

It changes the order. Get the porting answer from your lender before you agree a price, because it sets the ceiling on what you can spend next, and that in turn sets how much you need from your own sale.

ValuQ gives UK homeowners free, side-by-side property valuations from competing local estate agents, so you can see what several agents would list your home at before you speak to any of them, and put a realistic number into that calculation.

The short version

• Most residential mortgages are portable, so selling does not automatically cost you your rate.
• Porting needs a fresh application and a fresh affordability check, and it can be declined.
• Extra borrowing sits on a separate part at today's rates.
• Ask your lender for a porting illustration before you list, not after you accept an offer.