Foxtons claims buyers of off-plan homes can achieve over £26,000 in added value before even picking up the keys.

This claim comes at a time when off-plan sales are plummeting.

Hamptons says the share of new-build homes being sold before they are completed dropped to a 12-year low in 2025.

Some 33% of new homes in England and Wales were sold before construction was finished last year, down from 36% in 2024. 

However, Foxtons contends that over the last five years, new-build house prices across London have increased by an average of 0.23% per month, with this average monthly rate of growth climbing to as high as 0.4% in some boroughs.

It makes its calculation by suggesting that across the capital, the average new-build property currently costs £535,157. 

For the average new-build buyer purchasing off-plan, this means they could see this average house price climb to £561,412 over the estimated 21 months it takes to complete if they were to buy off-plan today. 

Foxtons says this represents an increase of 4.9%, or £26,255, before they’ve even moved in.

The agency’s new homes director, Amit Masrani, states: “International buyers … have long recognised the advantages of buying off-plan in London. 

“It provides the opportunity to secure a property in a globally desirable market at today’s price point, whilst benefiting from potential value growth before completion.

“We continue to see strong demand for high-quality London developments from overseas buyers who are taking a long-term view and who value the combination of stability, transparency and growth potential that the London market continues to offer.”