Flat 4, 6, Onslow Square has an Energy Performance Rating (EPC) of D. This is based on the most recent assessment, dated 26 Oct 2011.

The property is connected to mains gas and has partial secondary glazing. It is heated using community scheme.

Flat 4, 6, Onslow Square last changed hands on 11th October 2013, selling for £2,950,000. The transaction was logged as a leasehold flat by HM Land Registry.

In total it has sold 3 times since 1995.

The market for similar properties has dropped by 17.1% since October 2013.

• Sold Oct 2013£2,950,000
• Sold Jun 2002£940,000
• Sold Apr 2001£800,000

Land Registry records and our Estate Agent network show 29 sales of comparable properties within 280 metres of Flat 4, 6, Onslow Square since 2010.

Most recently, Flat 8, 20, Onslow Square, London, SW7 3NP, a leasehold flat, sold at £2,280,000 on the 23rd December 2025.

Read more about house prices in SW7.

• Sold Dec 2025£2,280,000 | 3 Bed FlatFlat 8, 20, Onslow Square, London, SW7 3NPFlat 8, 20, Onslow Square, London, SW7 3NP
• Sold Jun 2025£2,200,000 | 3 Bed FlatFlat 9, 14, Onslow Square, London, SW7 3NPFlat 9, 14, Onslow Square, London, SW7 3NP
• Sold Sep 2024£1,275,000 | 3 Bed FlatBasement, 109A, Onslow Square, London, SW7 3LUBasement, 109A, Onslow Square, London, SW7 3LU
• Sold Jul 2024£1,975,000 | 3 Bed FlatFlat 10, 14, Onslow Square, London, SW7 3NPFlat 10, 14, Onslow Square, London, SW7 3NP
• Sold Jun 2024£1,995,000 | 3 Bed FlatFlat 41, Melton Court, Onslow Crescent, London, SW7 3JHFlat 41, Melton Court, Onslow Crescent, London, SW7 3JH
• Sold Oct 2023£2,600,000 | 3 Bed FlatFlat 6, 89, Onslow Square, London, SW7 3LTFlat 6, 89, Onslow Square, London, SW7 3LT
• Sold Aug 2022£2,300,000 | 3 Bed FlatFlat 71, Melton Court, Onslow Crescent, London, SW7 3JHFlat 71, Melton Court, Onslow Crescent, London, SW7 3JH
• Sold Jan 2021£2,450,000 | 3 Bed FlatFlat 4, 89, Onslow Square, London, SW7 3LTFlat 4, 89, Onslow Square, London, SW7 3LT
• Sold Sep 2018£2,150,000 | 3 Bed FlatFlat 35, Melton Court, Onslow Crescent, London, SW7 3JQFlat 35, Melton Court, Onslow Crescent, London, SW7 3JQ
• Sold Sep 2017£632,000 | 3 Bed FlatFlat 1, 81, Onslow Square, London, SW7 3LTFlat 1, 81, Onslow Square, London, SW7 3LT
• Sold Mar 2017£2,500,000 | 3 Bed FlatFlat 2, 89, Onslow Square, London, SW7 3LTFlat 2, 89, Onslow Square, London, SW7 3LT
• Sold Jul 2016£3,600,000 | 3 Bed FlatFlat 8, 14, Onslow Square, London, SW7 3NPFlat 8, 14, Onslow Square, London, SW7 3NP
• Sold Nov 2015£3,200,000 | 3 Bed FlatFlat 6, 14, Onslow Square, London, SW7 3NPFlat 6, 14, Onslow Square, London, SW7 3NP
• Sold Sep 2014£2,900,000 | 3 Bed Flat7, Rose Square, London, SW3 6RS7, Rose Square, London, SW3 6RS
• Sold Jul 2014£1,999,000 | 3 Bed FlatFlat 4, 14, Onslow Square, London, SW7 3NPFlat 4, 14, Onslow Square, London, SW7 3NP
• Sold Aug 2013£2,600,000 | 3 Bed FlatFlat 10, 25, Onslow Square, London, SW7 3NJFlat 10, 25, Onslow Square, London, SW7 3NJ
• Sold Jun 2013£2,850,000 | 3 Bed FlatFlat 7, 97, Onslow Square, London, SW7 3LUFlat 7, 97, Onslow Square, London, SW7 3LU
• Sold Mar 2013£3,600,000 | 3 Bed FlatFlat 8, 25, Onslow Square, London, SW7 3NJFlat 8, 25, Onslow Square, London, SW7 3NJ
• Sold Sep 2012£518,619 | 3 Bed FlatFlat 3, 5, Onslow Square, London, SW7 3NJFlat 3, 5, Onslow Square, London, SW7 3NJ
• Sold Feb 2010£1,030,000 | 3 Bed FlatFlat 6, 6, Onslow Square, London, SW7 3NPFlat 6, 6, Onslow Square, London, SW7 3NP

Our analysis of the public data ranks Flat 4, 6, Onslow Square as the 125th largest and the 144th most expensive of the 321 addresses on Onslow Square, London, SW7.

Against the SW7 postcode district average, it is £48k less expensive than the typical property.

• Oratory Roman Catholic Primary School

  300 m away
• Our Lady of Victories RC Primary School

  500 m away
• Marlborough Primary School

  500 m away

• St. Thomas More Language College

  700 m away
• Chelsea Academy

  1.7 km away
• The London Oratory School

  1.8 km away

• South Kensington

  |

  200 m away
• Gloucester Road

  |

  700 m away
• Knightsbridge

  |

  1.1 km away

Environment Agency data suggests this area has a Very Low risk of flooding.