London’s Most Expensive Homes - From Record Sales to 1 Mayfair’s Billionaire Benchmark

London’s super-prime property market continues to set global records, with recent sales and upcoming developments pushing values into uncharted territory. Despite signs of caution in wider housing markets, the capital’s most exclusive addresses are commanding unprecedented figures and in some cases, reshaping what qualifies as luxury real estate.

Earlier this month, a Knightsbridge penthouse at the prestigious Knightsbridge Apartments received a £10 million price cut, reducing its asking price from £80 million to £70 million. The property, which spans 9,400 square feet with a 2,500 square foot roof terrace, features a glass-sided swimming pool, sauna and views over London landmarks including Big Ben and Hyde Park. It was previously the most expensive property to be publicly listed on Rightmove, underscoring how competitive the very top of the market has become.

Yet even this extraordinary penthouse is being overshadowed by newer entrants. At 1 Mayfair, a development led by billionaire John Caudwell, homes will start at around £35 million, with the scheme expected to become world’s most expensive residential building when measured by price per square metre. With just 29 units (including three penthouses, two mega-apartments, and five townhouses) the £2 billion project is due for completion in spring 2026. Industry observers note that the development is redefining what entry-level looks like in the luxury sector: here, even the smallest apartments are priced above many of London’s current trophy homes.

Historic mansions are also setting records. In Regent’s Park, The Holme (a 29,000 square-foot property surrounded by four acres of gardens) changed hands earlier this year for £138.9 million, placing it among the most expensive sales in London’s history. Prime streets in Mayfair, Belgravia and Kensington continue to maintain average prices between £16 million and £21 million, keeping central London firmly at the top of Europe’s costliest property charts.

Market data reflects a shifting picture. A mid-year survey from Beauchamp Estates revealed that while luxury sales face longer timelines, lettings activity at the top end of the market has doubled year-on-year, as ultra-wealthy buyers increasingly choose to rent while waiting for the right purchase. Meanwhile, LonRes reported that price reductions in prime central London rose by 60 per cent compared to the previous year, showing that even in the rarefied world of billionaire real estate, pricing strategy matters.

What unites all these properties is their scarcity and prestige. Whether a newly built penthouse with private amenities or a historic mansion with expansive grounds, London continues to offer some of the world’s most desirable homes. With developments like 1 Mayfair raising the bar yet again, the capital remains a benchmark for global wealth and a city where the definition of luxury is constantly being rewritten.