Lowndes Square is a residential garden square in Belgravia, London, SW1. Like much of Belgravia it is characterised by grand terraces with white stucco houses. The square runs parallel with Sloane Street to the east, east of the Harvey Nichols store and Knightsbridge tube station. It is home to some of the most expensive properties in the world. Russian businessman, Roman Abramovich bought two stucco houses in Lowndes Square in 2008 and, once completed, the merged house with a total of eight bedrooms is expected to be worth £150 million, exceeding the value of the previous most expensive house in London and the UK, at £80 million.
George Basevi designed many of the houses in the square. Nicolas Roeg and Donald Cammell's 1970 film Performance, starring Mick Jagger and James Fox, used interiors of Leonard Plugge's Lowndes Square house. The square was used as a setting in the Edward Frederic Benson novel The Countess of Lowndes Square. In Alan Hollinghurst's novel The Line of Beauty, the Ouradi family live on the square. The Pakistan High Commission is also located on this square.
Notables either born in Lowndes Square or who have lived there:
- William Lowndes (British politician) (1652–1724)
- Lord Alan Spencer-Churchill (1825–1873), businessman and great uncle of Winston Churchill
- Lord Haliburton (1832 - 1907), British civil servant, resided at No. 57.
- Claude Bowes-Lyon, 14th Earl of Strathmore and Kinghorne (1855–1944), landowner and maternal grandfather of Elizabeth II
- Geoffrey Lubbock, High Sheriff of the County of London, (1873–1932)
- H.D., American poet (1886–1961)
- Leonard Plugge (1889–1981), Parliamentarian
- Margaret Lowenfeld (1890–1973), child psychologist
- Oswald Mosley (1896–1980), British Fascist
- Eric Lubbock, 4th Baron Avebury, (1928–2016) Liberal parliamentarian
- Garland Anderson (1933–2001), American composer
- Roman Abramovich (born 1966), Russian tycoon
- Alfred Mond, 1st Baron Melchett, Parliamentarian (first Liberal and then Conservative) and Violet Mond, Baroness Melchett, humanitarian, activist, and social hostess
- "Revealed: Roman Abramovich's £150m palace – the most expensive house in Britain". The Daily Mail. April 27, 2008. Retrieved November 20, 2009.
- "Lowndes Square". London Gardens Online. Retrieved 4 February 2016.
- Morgan, Henry James, ed. (1903). Types of Canadian Women and of Women who are or have been Connected with Canada. Toronto: Williams Briggs. p. 142.