The gardens in the centre are open to the public, and their very large London Plane trees are among the oldest in central London, planted in 1789. One of the trees in the south east corner has been designated a Great Tree of London.
Whilst Berkeley Square was originally a mostly residential area, there now remains only one residential block on the square – number 48. The square is mostly offices, including a number of hedge funds and wealth management businesses.
The buildings around the square include several by other notable architects including Robert Adam, who designed Lansdowne House (since 1935 home of the Lansdowne Club) in the southwest corner of the square on Fitzmaurice Place. The daring staircase-hall of No. 44 is sometimes considered William Kent's masterpiece. Gunter's Tea Shop, founded under a different name in 1757, used to be located here.
There are a number of streets leading off the square including Berkeley Street, Curzon Street, and Hill Street. The gardens of Berkeley Square are Grade II listed on the Register of Historic Parks and Gardens.
In 2008, one of the square's trees was calculated to be the "most valuable street tree in Britain" by London Tree Officers Association, in terms of its size, health, historical significance and the number of people who live near to it.
The square is something of an accident. In 1696, Berkeley House on Piccadilly became Devonshire House when John Berkeley, 3rd Baron Berkeley of Stratton, sold it to William Cavendish, 1st Duke of Devonshire. As part of the agreement, Lord Berkeley undertook not to build on that part of the land he retained that lay directly behind the house, so keeping the Duke's view.
This agreement was continued when the Berkeley land was developed after 1730, and the gardens of Berkeley Square are the termination of that undeveloped strip; to the south the gardens of Lansdowne House were originally also part of it; they were replaced by the current south side of the square.
Residents of Berkeley Square have included:
- John Byng (1741), Vice-Admiral, Royal Navy. Byng's home was decorated by architect Isaac Ware.
- Horace Walpole lived at no. 11 1779 until his death in 1797.
- George Canning, UK Prime Minister (1827)—at no. 50
- Winston Churchill lived at no. 48 as a child
- Robert Clive of India—bought no. 45 in 1761 and committed suicide there in 1774.
- Sarah Child Villiers, Countess of Jersey (Lady Jersey), one of the famous patronesses of Almack's and leaders of the ton during the Regency era; heiress to the Child & Co. banking fortune—at no. 38.
- Charles Rolls, co-founder of Rolls-Royce, was born in Berkeley Square in 1877.
Famous former owners or residents of Lansdowne House include:
- John Stuart, 3rd Earl of Bute, British Prime Minister (1762–63)
- William Petty, 2nd Earl of Shelburne (later 1st Marquess of Lansdowne), British prime minister (1782–83)
- William Pitt the Younger, British prime minister (1783–1801, 1804–1806)
- William Waldorf Astor, 1st Viscount Astor, Richest man in America at the time (1891–1893)
- Archibald Primrose, 5th Earl of Rosebery, was a British Liberal statesman and Prime Minister (1894–1895)
- Harry Gordon Selfridge, founder of the Selfridges department store
- P.G. Wodehouse's character Bertie Wooster lives near Berkeley Square in a Berkeley St. flat along with his valet Jeeves, not far from the Drones Club.
- Harry Flashman, the vicious bully of Tom Brown's School Days and anti-hero of the Flashman Papers, had a marital home here with his wife Elsperth.
- Cathy Lane, Patty Lane's "identical cousin", is said to have lived here in the theme song to The Patty Duke Show.
- "Tomlinson", the title character of Rudyard Kipling's 1891 satirical poem, "gave up the ghost at his house in Berkeley Square".
- Peter Standish, a character from the play Berkeley Square written by John Balderston, about a Yankee who lives in a house on the square and is transported back to the 18th century. The play was produced as a movie in 1933, with Leslie Howard, and in 1951, and on television in 1959.
- In the 1949 comedy film Kind Hearts and Coronets, Lady Agatha D'Ascogne is made to fall to her death in Berkeley Square to accommodate a clever poetic parody.
- Lady Emily Ashton, created by author Tasha Alexander, lives primarily in her Berkeley Square residence during the Victorian period.
- The Marquis of Alverstoke, the main male character from the novel Frederica by Georgette Heyer.
Berkeley Square can be easily reached from Green Park Underground station on the Piccadilly, Jubilee and Victoria lines, and Bond Street Underground station on the Central and Jubilee lines. London Buses route 22 also passes through the square.
Berkeley Square is also one of the most popular locations for the Elektrobay charging points supplied by Elektromotive, with requests for additional charging points to be installed.
- 50 Berkeley Square, a building described as The Most Haunted House in London.
- Berkeley Square, the 1933 film starring Leslie Howard
- Berkeley Square, a 1998 TV mini-series produced by, and shown on, the BBC.
- The Ghosts of Berkeley Square, 1947 film starring Robert Morley and Felix Aylmer
- Lansdowne House
- "A Nightingale Sang in Berkeley Square"—a 1940 song written by Manning Sherwin and Eric Maschwitz, associated in England with singer Vera Lynn or in America with the Glenn Miller Band, and a 1979 film directed by Ralph Thomas.
- The Fleming Collection, a large private collection of Scottish art held in the square.
- List of eponymous roads in London
- Sykes, 104–111
- walksoflondon.co.uk—50 Berkeley Square, The Most Haunted House In London, accessed 2008-02-08.
- Historic England, "Berkeley Square (1000516)", National Heritage List for England, retrieved 22 March 2018
- 'Berkeley Square, North Side,' in Survey of London: Volume 40, the Grosvenor Estate in Mayfair, Part 2 (The Buildings), ed. F H W Sheppard (London: London County Council, 1980), 64–67, accessed November 21, 2015, online
- "Berkeley Square, North Side", Survey of London: volume 40: The Grosvenor Estate in Mayfair, Part 2 (The Buildings) (1980) at British History Online (date accessed 5 July 2009)
- "Berkeley Square and its neighbourhood", Old and New London: Volume 4 (1878) at British History Online (date accessed 5 July 2009)
- Sykes, Christopher Simon. Private Palaces: Life in the Great London Houses, Chatto & Windus, 1985