Do House Builders Know Who Their Next Buyer Will Be?

The market is asking house builders to work harder for every reservation this spring. On 1 June, Savills cut its 2026 forecast for mainstream UK house prices from a 2% rise to a 2% fall, citing higher mortgage rates and weaker demand. Nationwide recorded the first monthly price fall of the year in May. Stock is higher than usual, partly because landlords are selling up in the face of tighter regulation. The demand is still there; it has just become harder to convert, and that changes what good marketing has to do.

When demand was easy, a development could fill its early phases on portal traffic and a launch event. In a softer market, the buyers worth finding are the ones who haven’t started searching yet.

That is what TwentyCi’s propensity-to-move model is built to do. Because we track around 99% of UK residential moves, the model scores which households are likely to come to market in the next three to six months, before they instruct an agent or register interest in a scheme. In 2024, the top 10% of that model accounted for 57% of the homes that came to market. For a house builder, a large share of next year’s buyers can be identified now, and most fall into three groups.

The renter who’s ready to buy

Much new-build stock, and most shared ownership, is built for first-time buyers, and that buyer is rarely browsing new-build today. They’re in a rented flat, with the income to buy but no immediate prompt to start. Zoopla reported in May that first-time buyers are now targeting homes worth £10,000 more than a year ago, so the appetite is holding up even with affordability tight. Renters who can realistically afford a first home are identifiable by income, tenure and life stage long before they call an agent. 

The owner who has to sell first

Many reservations depend on a sale. The buyer wants the new home but can’t proceed until their current one is sold, which is where part-exchange and assisted-move offers earn their keep. The signal that matters is timing: which owners in a catchment are weeks away from putting their home on the market. That is what the propensity-to-move score identifies. Spotting an owner before they instruct an agent is the difference between opening the part-exchange conversation and inheriting it once a competitor already has. Get the timing right and the offer lands while the owner is actively thinking about the move. Get it wrong by a couple of months, and it’s wasted.

The tenant whose landlord is selling

The same regulation pushing landlords to sell is producing a steady supply of movers. When a landlord sells, the tenant has to move, and many of those tenants are would-be first-time buyers who would rather own than rent again. The data will identify the renters in a catchment who fit that profile, by income, tenure and life stage, and their numbers are rising as the rental market tightens. For a builder with the right stock at the right price, these are some of the most motivated buyers around.

The groups overlap, and they aren’t the whole picture. What they share is worth dwelling on: each becomes identifiable before it becomes obvious. More than 1.8 million households move in the UK each year, and the moment that decides a sales target is the short window when a household shifts from thinking about a move to actively making one. Reach a household too early, or too late, and the message is forgotten.

This costs nothing extra in media. It is a question of order: knowing which households in a catchment are moving before the wider market does, and putting the launch, the part-exchange offer and the first-time buyer message in front of them while the decision is live.

That is what TwentyCi gives a house builder: a way to see which households in a catchment fit each of these groups, ahead of the market, and to reach them across the channels you already use, from direct mail to digital advertising. The data is refreshed weekly, so it keeps pace with who is actually moving.

The demand for your next launch is already forming, and you can identify it before everyone else does.