If you are thinking about moving from your current home to a new build, start by checking how the move will be funded. Your available equity, existing mortgage terms and the developer’s timetable need to fit together before you commit to a reservation.
Existing homeowners are often described as second or third steppers. You may be looking for another bedroom, room to work from home or a layout that suits your family better. The mortgage planning needs to cover both the property you are leaving and the one you want to buy.
More enquiries from existing homeowners
Analysis by newhomesforsale.co.uk, reported by Mortgage Solutions on 16 October 2026, found that enquiries from existing homeowners about new-build properties rose by 23% in January to June 2026 compared with the preceding six months. The analysis was based on 58,000 homeowner enquiries. The South East recorded a 34% increase, while London recorded a 1% fall.
These are enquiries through one property portal, rather than completed purchases or a measure of the whole housing market. For anyone considering a move, the useful next step is to test whether the particular home and mortgage work for their circumstances.
1 Work out the deposit you can actually use
Start with a realistic sale price for your current home. Deduct the amount needed to repay your mortgage and any other borrowing secured against it. Then allow for the buying, selling and moving costs you intend to fund from those proceeds. MoneyHelper’s moving-cost guide covers legal fees, estate agency fees, mortgage charges, property transaction tax and removals.
For example, a £450,000 sale with £250,000 needed to repay the mortgage leaves £200,000 before costs. Your next deposit will be smaller if some of that money pays for the move or is kept as a cash reserve. This is an illustration, not an assessment of what you can borrow.
2 Compare porting with taking a new mortgage
You may be able to take your existing mortgage deal to the next property through a process called porting. However, MoneyHelper explains that moving still involves a mortgage application, including affordability checks and other lending criteria.
If you need extra borrowing, that part may be on a different rate with a different deal end date. Compare the combined payments and fees with a new mortgage for the whole amount, including any early repayment charges. Keeping an attractive existing rate is only one part of the calculation.
3 Check the lender accepts the property and deposit
Deposit requirements can differ between new-build houses and flats. Nationwide’s published new-build guidance, for example, sets different maximum lending percentages for the two property types. The appropriate lender also needs to be comfortable with the valuation, construction and relevant warranty or certification.
Ask your adviser to check the actual plot and development. A mortgage illustration based on the purchase price does not establish that the lender will accept every property at that price.
4 Have developer incentives checked before relying on them
A deposit contribution, cashback, paid legal fees or part-exchange offer can change the overall package. Tell your adviser and solicitor about every incentive. The UK Finance Disclosure Form records information about incentives and the property for the transaction.
Lender rules differ. Nationwide’s criteria, for example, treat part exchange as a financial incentive and restrict financial incentives at higher borrowing percentages. Do not assume that an offer from the developer will be acceptable to the mortgage lender.
For part exchange, compare the amount offered for your current home and the price of the new property with the likely outcome of selling separately. Include any fees saved and the value to you of the proposed timing.
5 Match the mortgage offer to the build timetable
Check the reservation terms, proposed exchange deadline and expected completion date with your adviser and solicitor. GOV.UK’s home-buying guide highlights that reservation fees may only be refundable in specified circumstances and construction dates can change.
Mortgage offers have expiry dates. Ask how long your chosen offer lasts, when that period starts and what happens if the build is delayed. Extension rules vary by lender; Nationwide’s current new-build arrangements, for example, do not provide a general extension option. An expected completion date is not a guarantee that the funding will remain available indefinitely.
6 Include the ongoing costs of the new home
Budget for the full household cost alongside the mortgage: Council Tax, utilities, insurance and any appropriate protection cover. Check the property’s energy information rather than assuming a particular saving.
Ask about service charges and estate management charges. A freehold house can still carry charges for shared roads or open spaces, as GOV.UK explains. Your solicitor should explain what you must pay, what the charges cover and how they can change.
Common questions from home movers
Does buying a new build remove the property chain?
You may still depend on selling your existing home. Buying from a developer does not, by itself, remove that part of the transaction. A part-exchange arrangement can change the position, subject to its terms.
Do I have to use the developer’s mortgage adviser?
No. GOV.UK’s guidance confirms that buyers are not obliged to use the mortgage adviser or legal representative recommended by a developer. You can choose your own adviser.
Talk to TLA Finance before reserving your next home
We can review your existing mortgage, available deposit and proposed purchase, then explain the mortgage options available through our service. Our mortgage advice team supports home movers across England, Scotland and Wales, including clients in Amersham and Buckinghamshire and London.
Tell us your approximate sale price, current mortgage balance and intended purchase price so we can start discussing the move. Request a call back from TLA Finance, call 01494 325 625 or email info@tlafinance.com.
This article provides general information. Mortgage availability depends on the lender’s assessment of your circumstances and the property. We will explain our service and any applicable fees before you proceed.
Your home may be repossessed if you do not keep up repayments on your mortgage.
Prepared with AI assistance using the sources linked above and reviewed through TLA Finance’s editorial approval process before publication. Lender criteria and property rules can change.
Illustrative photograph: David Walker / Unsplash. Existing licensed photograph from TLA Finance’s media library, used under the Unsplash Licence.
