Flat 3 43, Onslow Square, SW7 3LR

Flat 3 43 Onslow Square is a 199 m² / 2,142 sq ft flat in South Kensington. It sold for £4,100,000 in September 2021. Indexed forward to today's value, that sale is roughly £3,496k. Recent local prices imply a broad valuation context of £2,692k to £3,978k based on its internal area. The Land Registry and EPC data was last updated 1 June 2026.

Property data
Sale history
£4,100,000 on Sep 2021
Internal area
199 square metres (2,142 square feet) according to latest EPC inspection
Price per internal area

This property sold for £20,603 per square metre (£1,914 per square foot) in Sep 2021. Indexed forward to today's value, this is roughly £17,570 per square metre (£1,632 per square foot) .

Date Paid price Paid £/sqm Today's value Today's value £/sqm
Sep 2021 £4,100,000 £20,603 £3,496,460 £17,570

Calculated using the latest EPC internal area of 199 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 £3,496,460. 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 199 m², this implies a valuation between £2,692,000 and £3,978,000. 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
3
Type
Flat
Council tax band
H
Planning applications
Planning ref:
August 2022 LB/22/02707
Type:
Heritage application - conservation issues and listed buildings
Status:
Application approved
Address:
Flat 3, 43 Onslow Square, LONDON,
Description:
Internal alterations, including removal and addition of non load bearing partitions
EPC Inspections
Summary:
20 October 2020 - energy performance certificate grade C
Certificate:
View energy certificate on GOV.UK
Reason for EPC:
marketed sale
Tenure:
Owner-occupied
Property type:
2nd floor flat in an apartment block with 1 storeys , has 7 habitable rooms. Estimated year built before 1900
Area:
199 sqm (2,142 square foot) total internal area
Comments:
Walls: Solid brick, as built, no insulation (assumed). Roof: (another dwelling above). Heating: Community scheme.
Frequently asked questions

Flat 3 43 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 £3,496,460.
  • Based on an internal area of 199 m² and recent prices in South Kensington, this implies a lower and upper quartile range from £2,692,000 to £3,978,000, using HouseMetric's implied valuation methodology.

According to HM Land Registry price paid data, Flat 3 43 Onslow Square last sold for £4,100,000 in September 2021.

HouseMetric shows Flat 3 43 Onslow Square as 199 m² (2,142 sq ft), based on the latest internal area data available for this property. The bedroom count is shown as 3 bedrooms. Bedroom numbers can come from a previous estate agency listing, an EPC record, or an estimate based on the size of the property.

The latest EPC rating shown by HouseMetric is C, from an inspection dated 20 October 2020. EPC information comes from the public Energy Performance Certificate data for England and Wales.

When we last checked, Flat 3 43 Onslow Square was in council tax band H. Council Tax bands can change, so check the latest Valuation Office Agency Council Tax list.

Flat 3 43 Onslow Square is in postcode SW7 3LR, in South Kensington. You can also view HouseMetric's sold-price page for Onslow Square, SW7 3LR 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.