Flat 4, 40, Belsize Square has an Energy Performance Rating (EPC) of E. This is based on the most recent assessment, dated 06 Mar 2009.

The property is connected to mains gas and has single glazed windows. It is heated using a boiler and radiators (mains gas).

According to HM Land Registry, Flat 4, 40, Belsize Square was last sold on 5th January 2010 for £731,000 and was recorded as a leasehold flat.

The property has had 2 sales since 1995.

Since January 2010, the market for similar properties has risen by 75.4%.

• Sold Jan 2010£731,000
• Sold Oct 1999£312,500

According to the Land Registry and our network of Estate Agents, there have been 16 sales of properties similar to Flat 4, 40, Belsize Square within a radius of 260 metres since 2008.

The most recent example is 37A, Belsize Park Gardens, London, NW3 4JJ, a leasehold flat which sold for £2,180,000 on the 5th September 2025.

Read more about house prices in NW3.

• Sold Sep 2025£2,180,000 | 4 Bed Flat37A, Belsize Park Gardens, London, NW3 4JJ37A, Belsize Park Gardens, London, NW3 4JJ
• Sold Jul 2025£2,000,000 | 3 Bed Flat10A, Belsize Park, London, NW3 4ES10A, Belsize Park, London, NW3 4ES
• Sold Nov 2024£1,779,500 | 3 Bed Flat37C , Belsize Park Gardens, London, NW3 4JJ37C , Belsize Park Gardens, London, NW3 4JJ
• Sold Aug 2023£1,850,000 | 3 Bed FlatFlat 1, 8, Belsize Park Gardens, London, NW3 4LDFlat 1, 8, Belsize Park Gardens, London, NW3 4LD
• Sold Nov 2021£4,060,118 | 4 Bed FlatFlat 1, Belsize Studios, Glenilla Road, London, NW3 4ATFlat 1, Belsize Studios, Glenilla Road, London, NW3 4AT
• Sold Apr 2021£1,475,000 | 4 Bed Flat26B , Belsize Park Gardens, London, NW3 4LH26B , Belsize Park Gardens, London, NW3 4LH
• Sold Sep 2020£1,885,000 | 3 Bed FlatFlat 2, 35, Belsize Park Gardens, London, NW3 4JJFlat 2, 35, Belsize Park Gardens, London, NW3 4JJ
• Sold Jun 2018£2,263,104 | 3 Bed FlatApartment 7, 21, Belsize Lane, London, NW3 5ASApartment 7, 21, Belsize Lane, London, NW3 5AS
• Sold Mar 2016£1,835,500 | 4 Bed Flat12C , Belsize Square, London, NW3 4HT12C , Belsize Square, London, NW3 4HT
• Sold Jan 2015£1,960,000 | 3 Bed FlatFlat 3, 18, Belsize Square, London, NW3 4HTFlat 3, 18, Belsize Square, London, NW3 4HT
• Sold Jan 2014£1,800,000 | 3 Bed FlatFlat 3, 15, Belsize Park Gardens, London, NW3 4JGFlat 3, 15, Belsize Park Gardens, London, NW3 4JG
• Sold Aug 2012£1,253,000 | 3 Bed FlatFlat 1, 16, Belsize Park Gardens, London, NW3 4LDFlat 1, 16, Belsize Park Gardens, London, NW3 4LD
• Sold Jun 2012£280,100 | 4 Bed FlatFlat A, 38, Belsize Avenue, London, NW3 4AHFlat A, 38, Belsize Avenue, London, NW3 4AH
• Sold Mar 2012£1,450,000 | 3 Bed FlatFlat 2, 13, Belsize Park Gardens, London, NW3 4JGFlat 2, 13, Belsize Park Gardens, London, NW3 4JG
• Sold Dec 2008£940,000 | 3 Bed FlatFlat 3, 3, Belsize Park Gardens, London, NW3 4LBFlat 3, 3, Belsize Park Gardens, London, NW3 4LB
• Sold Jul 2008£1,390,000 | 4 Bed FlatFlat 1, 29, Belsize Park Gardens, London, NW3 4JHFlat 1, 29, Belsize Park Gardens, London, NW3 4JH

Our network of Estate Agents reports 2 lets within 260 metres of Flat 4, 40, Belsize Square over the last 2 years.

Most recently, 3B , Lancaster Drive, London, NW3 4EY, a leasehold flat, was let by Fine Living in February 2025.

• 
  Let agreed Feb 2025£ Undisclosed | 2 Bed Flat3B , Lancaster Drive, London, NW3 4EY3B , Lancaster Drive, London, NW3 4EY
• 
  Let agreed Mar 2024£ Undisclosed | 1 Bed Flat3A , Lancaster Drive, London, NW3 4EY3A , Lancaster Drive, London, NW3 4EY

•Nearby is defined as the radius comprising the nearest 2,000 addresses.

Belsize Square, London, NW3 has a total of 264 addresses. According to our analysis of all the public data, Flat 4, 40, Belsize Square is the 18th largest and the 23rd most expensive property on the street.

When compared to the postcode district it is £418k more expensive than the average property in NW3.

• Rosary Catholic Primary School

  500 m away
• Holy Trinity CofE Primary School, NW3

  600 m away
• St Paul's Church of England Primary School

  800 m away

• The UCL Academy

  700 m away
• Haverstock School

  1.1 km away
• Harris Academy St John's Wood

  1.2 km away

• Belsize Park

  |

  500 m away
• Swiss Cottage

  |

  600 m away
• Finchley Road

  |

  700 m away

According to data from the Environment Agency, the flood risk in this area is considered to be Very Low.