9, Onslow Square has an Energy Performance Rating (EPC) of C. This is based on the most recent assessment, dated 11 Jun 2021.

The property is not connected to mains gas and has full secondary glazing. It is heated using electric storage heaters.

Land Registry records and our Estate Agent network show 473 sales within 280 metres of 9, Onslow Square since 2007.

Most recently, Flat 2, 11, Onslow Square, London, SW7 3NJ, a leasehold flat, sold at £2,750,000 on the 20th November 2025.

Read more about house prices in SW7.

• Sold Nov 2025£2,750,000 | 3 Bed FlatFlat 2, 11, Onslow Square, London, SW7 3NJFlat 2, 11, Onslow Square, London, SW7 3NJ
• Sold Nov 2024£2,825,000 | 3 Bed FlatFlat 2, 23, Onslow Square, London, SW7 3NJFlat 2, 23, Onslow Square, London, SW7 3NJ
• Sold Oct 2024£560,000 | 3 Bed FlatFlat 12, 25, Onslow Square, London, SW7 3NJFlat 12, 25, Onslow Square, London, SW7 3NJ
• Sold Sep 2024£3,700,000 | 4 Bed Flat2, Onslow Square, London, SW7 3NP2, Onslow Square, London, SW7 3NP
• Sold Aug 2024£4,100,000 | 4 Bed Flat4, Onslow Square, London, SW7 3NP4, Onslow Square, London, SW7 3NP
• Sold Jul 2023£1,600,000 | 2 Bed FlatFlat 11, 25, Onslow Square, London, SW7 3NJFlat 11, 25, Onslow Square, London, SW7 3NJ
• Sold May 2023£2,800,000 | 2 Bed FlatFlat 3, 23, Onslow Square, London, SW7 3NJFlat 3, 23, Onslow Square, London, SW7 3NJ
• Sold Aug 2022£3,600,000 | 3 Bed FlatFlat 1, 17, Onslow Square, London, SW7 3NJFlat 1, 17, Onslow Square, London, SW7 3NJ
• Sold Jun 2021£1,800,000 | 2 Bed FlatFlat 7, 6, Onslow Square, London, SW7 3NPFlat 7, 6, Onslow Square, London, SW7 3NP
• Sold Mar 2021£2,300,000 | 3 Bed Flat1, Onslow Square, London, SW7 3NJ1, Onslow Square, London, SW7 3NJ
• Sold Oct 2020£560,000 | 1 Bed FlatFlat 1A, 25, Onslow Square, London, SW7 3NJFlat 1A, 25, Onslow Square, London, SW7 3NJ
• Sold Mar 2016£4,400,000 | 3 Bed Flat19, Onslow Square, London, SW7 3NJ19, Onslow Square, London, SW7 3NJ
• Sold Dec 2015£2,850,000 | 3 Bed FlatFlat 4, 5, Onslow Square, London, SW7 3NJFlat 4, 5, Onslow Square, London, SW7 3NJ
• Sold Oct 2013£2,950,000 | 3 Bed FlatFlat 4, 6, Onslow Square, London, SW7 3NPFlat 4, 6, 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 Feb 2013£2,300,000 | 3 Bed FlatFlat 5, 5, Onslow Square, London, SW7 3NJFlat 5, 5, 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
• Sold Jun 2008£4,000,000 | 4 Bed House9, Sydney Place, London, SW7 3NL9, Sydney Place, London, SW7 3NL
• Sold Jun 2007£1,352,000 | 2 Bed FlatFlat 3, 11, Onslow Square, London, SW7 3NJFlat 3, 11, Onslow Square, London, SW7 3NJ

Our analysis of the public data ranks 9, Onslow Square as the 319th largest and the 314th most expensive of the 321 addresses on Onslow Square, London, SW7.

Against the SW7 postcode district average, it is £1.322m less expensive than the typical property.

• Oratory Roman Catholic Primary School

  300 m away
• Marlborough Primary School

  400 m away
• Our Lady of Victories RC Primary School

  500 m away

• St. Thomas More Language College

  700 m away
• Chelsea Academy

  1.8 km away
• The London Oratory School

  1.9 km away

• South Kensington

  |

  200 m away
• Gloucester Road

  |

  700 m away
• Knightsbridge

  |

  1.0 km away

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