Flat 2, 21, Belsize Avenue has an Energy Performance Rating (EPC) of D. This is based on the most recent assessment, dated 11 Oct 2010.

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

The most recent sale of Flat 2, 21, Belsize Avenue completed on 18th July 2000 at £360,000 and was recorded by HM Land Registry as a leasehold flat.

Since 1995 the property has sold twice.

Since 2016 61 properties similar to Flat 2, 21, Belsize Avenue have sold within a radius of 270 metres, per the Land Registry and our network of Estate Agents.

The latest, on the 17th April 2026, was Flat 7, 27, Belsize Avenue, London, NW3 4BL, a leasehold flat which sold for £700,000.

Read more about house prices in NW3.

• Sold Apr 2026£700,000 | 3 Bed FlatFlat 7, 27, Belsize Avenue, London, NW3 4BLFlat 7, 27, Belsize Avenue, London, NW3 4BL
• Sold Jul 2025£810,000 | 3 Bed FlatFlat 34, Belsize Court, Wedderburn Road, London, NW3 5QJFlat 34, Belsize Court, Wedderburn Road, London, NW3 5QJ
• Sold Jun 2025£887,500 | 2 Bed Flat12B, Belsize Park Gardens, London, NW3 4LD12B, Belsize Park Gardens, London, NW3 4LD
• Sold May 2025£947,500 | 3 Bed Flat35G, Belsize Avenue, London, NW3 4BN35G, Belsize Avenue, London, NW3 4BN
• Sold Sep 2024£910,500 | 2 Bed FlatFlat 2, 47, Belsize Square, London, NW3 4HNFlat 2, 47, Belsize Square, London, NW3 4HN
• Sold Aug 2024£820,000 | 3 Bed FlatFlat 16, Glenloch Court, Glenmore Road, London, NW3 4DDFlat 16, Glenloch Court, Glenmore Road, London, NW3 4DD
• Sold Aug 2024£985,000 | 3 Bed FlatFlat 95, Hillfield Court, Belsize Avenue, London, NW3 4BEFlat 95, Hillfield Court, Belsize Avenue, London, NW3 4BE
• Sold Nov 2023£835,000 | 3 Bed FlatFlat 89, Hillfield Court, Belsize Avenue, London, NW3 4BEFlat 89, Hillfield Court, Belsize Avenue, London, NW3 4BE
• Sold Sep 2023£920,000 | 3 Bed FlatFlat 103, Hillfield Court, Belsize Avenue, London, NW3 4BEFlat 103, Hillfield Court, Belsize Avenue, London, NW3 4BE
• Sold Jan 2023£960,000 | 3 Bed Flat20, Tudor Close, London, NW3 4AG20, Tudor Close, London, NW3 4AG
• Sold Jan 2023£1,160,000 | 3 Bed FlatFlat 6, Glenloch Court, Glenmore Road, London, NW3 4DDFlat 6, Glenloch Court, Glenmore Road, London, NW3 4DD
• Sold Nov 2022£765,000 | 3 Bed FlatFlat 24, 15, Belsize Avenue, London, NW3 4BLFlat 24, 15, Belsize Avenue, London, NW3 4BL
• Sold Sep 2022£898,500 | 3 Bed FlatFlat E, 44, Belsize Avenue, London, NW3 4AEFlat E, 44, Belsize Avenue, London, NW3 4AE
• Sold Dec 2021£800,000 | 3 Bed Flat56, Tudor Close, London, NW3 4AG56, Tudor Close, London, NW3 4AG
• Sold Sep 2021£1,180,000 | 3 Bed FlatFlat 1, 23, Belsize Park, London, NW3 4DUFlat 1, 23, Belsize Park, London, NW3 4DU
• Sold Dec 2019£1,090,000 | 3 Bed FlatFlat 5, 46, Belsize Avenue, London, NW3 4AEFlat 5, 46, Belsize Avenue, London, NW3 4AE
• Sold May 2019£1,160,000 | 3 Bed FlatFlat 1, 47, Belsize Square, London, NW3 4HNFlat 1, 47, Belsize Square, London, NW3 4HN
• Sold Oct 2017£1,232,000 | 3 Bed FlatFlat 2, 25, Belsize Park, London, NW3 4DUFlat 2, 25, Belsize Park, London, NW3 4DU
• Sold Jul 2017£980,000 | 3 Bed FlatFlat 8, Glenloch Court, Glenmore Road, London, NW3 4DDFlat 8, Glenloch Court, Glenmore Road, London, NW3 4DD
• Sold Jul 2016£1,046,175 | 3 Bed FlatFlat 5, Glenloch Court, Glenmore Road, London, NW3 4DDFlat 5, Glenloch Court, Glenmore Road, London, NW3 4DD

Of the 446 addresses on Belsize Avenue, London, NW3, Flat 2, 21, Belsize Avenue comes out as the 127th largest and the 129th most expensive in our analysis of the public data.

It is also £472k less expensive than the average property across the NW3 district.

• Rosary Catholic Primary School

  400 m away
• Fitzjohn's Primary School

  600 m away
• Holy Trinity CofE Primary School, NW3

  600 m away

• The UCL Academy

  900 m away
• Haverstock School

  1.3 km away
• Harris Academy St John's Wood

  1.4 km away

• Belsize Park

  |

  400 m away
• Finchley Road

  |

  700 m away
• Hampstead Heath

  |

  700 m away

The flood risk here is rated Very Low, based on Environment Agency data.