Moving Home Mortgage Guide: Porting vs Switching UK
Moving home raises real mortgage questions. Should you port your current deal, move to a new lender, or borrow more for a bigger place? Here is what each choice costs.
Moving home is one of the bigger money decisions you will make, and your mortgage sits at the heart of it. Perhaps you are trading up to a larger family home. Perhaps you are scaling down now the children have flown the nest, or the move is simply about a new job in a new town. The mortgage you pick for the next place can save you thousands of pounds across its life, or quietly cost you the same again if the fit is wrong. So before you commit, it is worth understanding the choice in front of you: porting your mortgage (carrying your current deal over to the new home), moving to a new lender, or a mix of the two.
A lot of home movers assume they are tied to their current lender. Usually you are not. Lenders compete hard for UK mortgage business, and the deal you signed two or three years ago may already have been overtaken by something better. Porting really comes into its own in one case: you are locked into a low fixed rate and leaving early would land you with early repayment charges. Beyond that, the route that wins depends on how much time is left on your deal, your loan-to-value (how big your mortgage is next to what the property is worth), and how much extra you need to borrow for the new place.
This guide walks through each option open to home movers in the UK. It sets out how porting works, when moving to a new lender is the better call, how to borrow more as you climb the ladder, the full costs including stamp duty, and a timeline that runs from an accepted offer to the day you get the keys. Keep our stamp duty calculator and borrowing calculator to hand as you read, so you can test real figures against your own move.
Your mortgage options when moving home
When you sell one home and buy another, you have three main mortgage routes. You can port your existing deal across to the new property. You can clear it and take a fresh mortgage with a different lender. Or you can port what you have and top it up with extra borrowing. Each route lands you on a different cost and a different rate.
Which one is best for you turns on how far through your current deal you are, how much equity you have built up, and how the price of the new property compares with your outstanding balance. A whole-of-market broker can put all three side by side, so you see the monthly payment and the total cost over the deal, not just the headline rate.
When you sell one home and buy another, you have three main mortgage routes: port your existing deal, clear it and take a completely new mortgage, or port and top up with extra borrowing. Our moving home mortgages hub covers each route in detail.
Which one suits you depends on how far through your current deal you are, how much equity you hold, and how the new property price compares with your outstanding balance. A whole-of-market broker can model all three so you can weigh the monthly and total costs.
Port your mortgage
- Carry your existing deal, with the same rate, term and balance, over to the new property. It fits well when you are part-way through a competitive fixed rate and want to avoid early repayment charges.
Switch to a new lender
- Pay off your current mortgage when the sale completes and start a brand-new deal with a different lender. This tends to work best once your existing deal has ended, or when the wider market is pricing lower than the rate you are on.
Port and top up
- Hold your existing deal on the current balance and borrow a further slice from the same lender at a new rate. Useful when you are buying somewhere more expensive but want to protect the original balance from early repayment charges.
Start planning early
Speak to a broker as soon as your property search begins. If you already know your budget and your mortgage options before you make an offer, you negotiate with sellers from a much stronger footing.
Porting your mortgage explained
Porting means moving your current mortgage deal onto a new property. Your interest rate, the time left on the deal and the outstanding balance all stay put. The one thing that changes is the security behind the loan, which moves from your old home to the new one. Most major UK lenders let you port, but it is never a certainty. You still have to pass their affordability and valuation checks on the property you are buying.
Porting pays off when you are part-way through a competitive fixed rate and the early repayment charge for leaving would hurt. Picture two years left on a five-year fix at 3.8%, while the sharpest new deals sit near 4.5%. Keeping your existing rate holds your monthly payment down.
Porting means moving your current mortgage deal onto a new property. The rate, the time left and the outstanding balance all stay the same. Only the security changes, moving from your old home to the new one. For a full walkthrough, see our porting your mortgage guide.
Most major UK lenders allow porting, though it is not a given. You still have to pass affordability and valuation checks on the new property, which makes a port a fresh application in all but name, judged against the lender’s current criteria.
When porting works well vs when it does not
| Porting makes sense | Porting may not work |
|---|---|
| You are part-way through a competitive fixed rate | Your deal is close to ending, so early repayment charges are low or zero |
| Early repayment charges would be steep (often 2% to 5% of the balance) | Sharper rates are available on the open market |
| You are moving to a home of similar or lower value | You need to borrow a lot more than your current balance |
| Your lender’s current criteria still fit your circumstances | Your circumstances have shifted and you no longer meet the lender’s criteria |
Porting is not automatic
Your lender may advertise porting as a built-in feature, yet they still reassess your income, your outgoings and your credit history against their current lending rules. If something has moved since you first borrowed, perhaps you have become self-employed or taken on other debt, the port can still be refused.
Getting a new mortgage when you move
If your current deal is due to end in the next few months, or the market is pricing well below what you pay now, moving to a new lender is often the better call. You clear the old mortgage when your current home sells, then start a fresh deal on the new one. That puts the whole market within reach, rather than the single shelf of products your existing lender happens to stock.
Looking across the whole market counts for even more once your equity has grown. A lower loan-to-value moves you into better rate bands, and over a two or five-year fix that gap can add up to real money. A broker checks 90+ lenders in minutes and can flag deals with free valuations or cashback that help cover the cost of switching.
If your current deal is ending soon, or the market is offering rates well below what you pay now, moving to a new lender is often the smarter play. You clear the old mortgage once your current home sells, then take a fresh deal on the new one.
Looking across the whole market counts for more once your equity has grown. A lower loan-to-value moves you into better rate bands, and over a two or five-year fix those savings can be sizeable.
Why switching could save you money
Borrowing more when moving up the ladder
Most people who move are trading up to a pricier property, so they need to borrow more than their current balance. Even after you fold in the equity freed up by selling the old home, a gap is usually left to fill. Lenders assess that extra borrowing with a fresh affordability check, weighing your income, your regular commitments and your credit record.
When you port, the extra borrowing sits on a separate sub-account with its own rate and term. When you switch lender outright, the whole sum is judged as one new mortgage. Either way, knowing your borrowing limit before you book viewings keeps your budget grounded in what you can actually afford.
Most people who move are buying somewhere more expensive, so they need to borrow more than their current balance. Even after the equity from the sale goes in, a gap usually remains. Our guide on how much you can borrow sets out the affordability rules lenders work to.
When you port, the extra borrowing sits on a separate sub-account with its own rate and term. When you switch lender outright, the full amount is assessed as a single new mortgage.
How to work out what you can afford
- 01
Calculate your equity
Take your current property’s market value and take off the mortgage you still owe. What remains is your equity. Our LTV calculator gives you a quick estimate.
- 02
Estimate your deposit
Once selling costs come out, the equity from your sale becomes the deposit on your next home. A bigger deposit means a lower LTV, and a lower LTV opens up better rates.
- 03
Check your borrowing capacity
Most lenders will advance somewhere around 4 to 4.5 times your household income. Our borrowing calculator shows roughly where you stand.
- 04
Add deposit and borrowing together
Add your deposit to your maximum borrowing and you have a rough ceiling on what you can pay. A broker can sharpen that number against the criteria of specific lenders.
Example: moving from a £300,000 to a £450,000 property
If you owe £180,000 on a property worth £300,000, you hold £120,000 of equity. After selling costs of around £5,000, your deposit is £115,000. Buying at £450,000 then needs a mortgage of £335,000, which works out at a 74% LTV and sits within competitive rate bands.
Costs to budget for when moving home
Moving home carries more upfront costs than a remortgage, so budget carefully from the start. Stamp duty land tax is usually the biggest single expense. After that come estate agent fees on your sale, conveyancing on both properties, and any early repayment charge if you leave your current deal early.
Some of these costs are fixed, some scale with the property price, and a few you can negotiate. Pin down the total early and you can set a realistic purchase budget, with no nasty surprises landing close to completion.
Moving home carries more upfront costs than a remortgage, so budget carefully. Stamp duty is usually the largest single expense, followed by estate agent fees, conveyancing, and any early repayment charge.
Some costs are fixed, some scale with the price, and a few are negotiable. A clear picture early on lets you set a realistic purchase budget.
Full cost breakdown for home movers
Property purchase costs
- Stamp duty (SDLT): varies by price band, so use our [stamp duty calculator](/calculators/stamp-duty) for an instant estimate
- Conveyancing (buying side): £1,000 to £2,000 including searches and Land Registry fees
- Survey or valuation: £250 to £700 depending on the type (condition report, homebuyer, or full structural)
- Mortgage arrangement fee: £500 to £2,000 (can often be added to the loan)
Property sale costs
- Estate agent fees: typically 1% to 1.5% of the sale price plus VAT
- Conveyancing (selling side): £500 to £1,000
- Early repayment charge: 1% to 5% of your outstanding balance if leaving a deal early
- Energy performance certificate (EPC): £60 to £120 if yours has expired
Example costs on a £400,000 purchase
The moving home mortgage timeline
From an accepted offer to picking up the keys, a typical home move takes eight to twelve weeks. The mortgage application itself is usually the quickest part, with most lenders issuing a formal offer within two to four weeks. The rest of the time goes on conveyancing searches, working through any chain, and lining up an exchange and completion date.
Buying chain-free or from a new-build developer can shave weeks off that. If you are selling at the same time, lining up both transactions matters, since a mismatch can leave you needing bridging finance or somewhere to stay in between.
From an accepted offer to picking up the keys, a typical home move takes eight to twelve weeks. The mortgage application is usually the quickest part, with most lenders issuing a formal offer within two to four weeks. For ways to speed things up, see our guide to chain-free buying.
Buying chain-free or from a new-build developer can speed things up. If you are selling too, aligning both transactions is what keeps you clear of bridging finance or temporary accommodation.
Step-by-step timeline
- 01
Weeks 1–2: Offer accepted and mortgage application
Your broker submits the mortgage application with supporting documents. The lender instructs a valuation on the new property, which is usually completed within a few days.
- 02
Weeks 2–4: Mortgage offer issued
The lender assesses your application, reviews the valuation, and issues a formal mortgage offer. Your solicitor receives a copy and begins the conveyancing process.
- 03
Weeks 4–8: Conveyancing and searches
Your solicitor carries out local authority searches, environmental checks, and title reviews. They raise enquiries with the seller’s solicitor and work through any issues that arise.
- 04
Weeks 8–10: Exchange of contracts
Once all searches are clear and both parties are satisfied, contracts are exchanged. This is the point at which the purchase becomes legally binding and a completion date is set.
- 05
Weeks 10–12: Completion and keys
On completion day the mortgage funds are released, the purchase price is paid, and you collect the keys. Your solicitor registers the new ownership with the Land Registry.
Get your mortgage agreed in principle before you start viewing, and you can move fast when the right home turns up. Sellers take your offer more seriously too.
Frequently asked questions
- Regulator
- FCA register
- Updated
- 24 February 2026
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Moving home? Let’s find your best mortgage option
Our advisers compare deals from 90+ lenders and tell you plainly whether porting, switching, or a mix of the two works out best for you. We handle the paperwork and keep your move on track from application through to completion.