New data pointing to a marked decline in new-build purchasers across London signals more than a passing soft patch — it marks a structural shift in where and how UK buyers are choosing to invest. Buyers who might once have paid a premium for a shiny riverside apartment in Nine Elms or Canary Wharf are increasingly walking away, deterred by a combination of stretched affordability, punitive service charges, ground rent uncertainty and a stamp duty regime that disproportionately penalises additional-property purchases in the capital. For an industry still reliant on London as its flagship market, this is a red flag that developers, lenders and investors cannot afford to ignore.