Property data
Sale history
Date Paid price Annual growth After inflation
Sep 2012 £518,619 -31.7% -33.7%
Oct 2009 £1,600,000 5.8% 3.2%
May 2005 £1,248,000 na na
Internal area
112 square metres (1,206 square feet) according to latest EPC inspection
Price per internal area

This property sold for £4,630 per square metre (£430 per square foot) in Sep 2012. Indexed forward to today's value, this is roughly £6,367 per square metre (£592 per square foot) .

Date Paid price Paid £/sqm Today's value Today's value £/sqm
Sep 2012 £518,619 £4,631 £713,136 £6,367
Oct 2009 £1,600,000 £14,286 £1,953,973 £17,446
May 2005 £1,248,000 £11,143 £2,463,922 £21,999

Calculated using the latest EPC internal area of 112 m². Earlier sale dates may not have had the same measured area available.

Valuation
The most recent sale price indexed forward to today's value is £713,136. This is one data point to inform the valuation. Another method is the valuation implied by what comparable homes are selling for. Homes in South Kensington are now selling for between £13,530 and £19,990 per square metre (£1,256 and £1,857 per square foot). Based on an internal area of 112 m², this implies a valuation between £1,515,000 and £2,239,000. Treat this as context only. For a valuation using hand-picked comparable sales, use the Advanced search tool — create a shortlist of similar condition homes, then export a valuation report.
Bedrooms
na
Type
Flat
Council tax band
na
EPC Inspections
Summary:
07 January 2022 - energy performance certificate grade D
Certificate:
View energy certificate on GOV.UK
Reason for EPC:
marketed sale
Tenure:
Private rental
Property type:
2nd floor flat in an apartment block with 1 storeys , has 5 habitable rooms. Estimated year built 1900 to 1929
Area:
117 sqm (1,259 square foot) total internal area
Comments:
Walls: Solid brick, as built, no insulation (assumed). Roof: (another dwelling above). Heating: Community scheme.

Summary:
24 June 2009 - energy performance certificate grade E
Reason for EPC:
None
Tenure:
Private rental
Property type:
None , has 3 habitable rooms. Estimated year built before 1900
Area:
112 sqm (1,206 square foot) total internal area
Comments:
Frequently asked questions

Flat 3 5 Onslow Square is worth whatever price a willing buyer and seller agree upon. However, the following can provide useful context.

  • HouseMetric estimates the most recent sale price indexed forward to today's value is £713,136.
  • Based on an internal area of 112 m² and recent prices in South Kensington, this implies a lower and upper quartile range from £1,515,000 to £2,239,000, using HouseMetric's implied valuation methodology.

According to HM Land Registry price paid data, Flat 3 5 Onslow Square last sold for £518,619 in September 2012.

HouseMetric shows Flat 3 5 Onslow Square as 112 m² (1,206 sq ft), based on the latest internal area data available for this property.

The latest EPC rating shown by HouseMetric is D, from an inspection dated 07 January 2022. EPC information comes from the public Energy Performance Certificate data for England and Wales.

Flat 3 5 Onslow Square is in postcode SW7 3NJ, in South Kensington. You can also view HouseMetric's sold-price page for Onslow Square, SW7 3NJ or analysis of the South Kensington property market.

HouseMetric combines HM Land Registry price paid data, Energy Performance Certificate data and Ordnance Survey/open data. The data were last updated 1 June 2026. Figures such as indexed values and local valuation ranges are calculated estimates for context, while official records can change as public datasets are updated.

For more detail on HouseMetric data sources, update frequency and valuation methods, see the HouseMetric FAQs.