Flat C, 23, Belsize Avenue has an Energy Performance Rating (EPC) of D. This is based on the most recent assessment, dated 26 Aug 2020.

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

Land Registry records and our Estate Agent network show 65 sales of comparable properties within 270 metres of Flat C, 23, Belsize Avenue since 2015.

Most recently, Flat 4, Roscommon House 2, Lyndhurst Gardens, London, NW3 5NP, a leasehold flat, sold at £1,200,000 on the 18th December 2025.

Read more about house prices in NW3.

• Sold Dec 2025£1,200,000 | 3 Bed FlatFlat 4, Roscommon House 2, Lyndhurst Gardens, London, NW3 5NPFlat 4, Roscommon House 2, Lyndhurst Gardens, London, NW3 5NP
• Sold Aug 2025£1,050,000 | 3 Bed Flat76, Belsize Lane, London, NW3 5BJ76, Belsize Lane, London, NW3 5BJ
• Sold Jun 2025£1,150,000 | 3 Bed FlatFlat 4, 28, Belsize Park Gardens, London, NW3 4LHFlat 4, 28, Belsize Park Gardens, London, NW3 4LH
• Sold Mar 2025£1,050,000 | 3 Bed FlatFlat 3, 20, Ornan Road, London, NW3 4PXFlat 3, 20, Ornan Road, London, NW3 4PX
• Sold Jun 2024£1,137,500 | 3 Bed FlatFlat 44, Belsize Court, Wedderburn Road, London, NW3 5QHFlat 44, Belsize Court, Wedderburn Road, London, NW3 5QH
• Sold May 2024£1,075,000 | 3 Bed FlatFlat 3, Belsize Court, Wedderburn Road, London, NW3 5QLFlat 3, Belsize Court, Wedderburn Road, London, NW3 5QL
• Sold Apr 2024£1,325,000 | 3 Bed FlatFlat 33, Belsize Court, Wedderburn Road, London, NW3 5QNFlat 33, Belsize Court, Wedderburn Road, London, NW3 5QN
• Sold Feb 2024£1,090,000 | 3 Bed FlatFlat 1B, Wedderburn House 1, Wedderburn Road, London, NW3 5QRFlat 1B, Wedderburn House 1, Wedderburn Road, London, NW3 5QR
• Sold Dec 2023£1,312,500 | 3 Bed FlatFlat 48, Belsize Court, Wedderburn Road, London, NW3 5QHFlat 48, Belsize Court, Wedderburn Road, London, NW3 5QH
• Sold Apr 2023£1,085,000 | 3 Bed FlatFlat 47, Belsize Court, Wedderburn Road, London, NW3 5QPFlat 47, Belsize Court, Wedderburn Road, London, NW3 5QP
• Sold Feb 2023£1,200,000 | 3 Bed FlatFlat 5, Belsize Court, Wedderburn Road, London, NW3 5QLFlat 5, Belsize Court, Wedderburn Road, London, NW3 5QL
• Sold Jan 2023£1,420,000 | 3 Bed Flat25C , Belsize Avenue, London, NW3 4BL25C , Belsize Avenue, London, NW3 4BL
• Sold Oct 2022£1,250,000 | 3 Bed FlatFlat 7, Belsize Court, Wedderburn Road, London, NW3 5QLFlat 7, Belsize Court, Wedderburn Road, London, NW3 5QL
• Sold Aug 2022£1,510,000 | 3 Bed FlatFlat 1, 26, Belsize Avenue, London, NW3 4AUFlat 1, 26, Belsize Avenue, London, NW3 4AU
• Sold Feb 2022£1,600,000 | 3 Bed Flat6, Belsize Park Gardens, London, NW3 4LD6, Belsize Park Gardens, London, NW3 4LD
• Sold Mar 2021£1,123,296 | 3 Bed FlatFlat B, 23, Belsize Avenue, London, NW3 4BLFlat B, 23, Belsize Avenue, London, NW3 4BL
• Sold Mar 2021£1,280,000 | 3 Bed FlatFlat 2, 20, Belsize Park Gardens, London, NW3 4LHFlat 2, 20, Belsize Park Gardens, London, NW3 4LH
• Sold Mar 2018£1,160,000 | 3 Bed Flat44B , Belsize Square, London, NW3 4HN44B , Belsize Square, London, NW3 4HN
• Sold Sep 2015£1,295,000 | 3 Bed FlatFlat 2, 28, Belsize Park Gardens, London, NW3 4LHFlat 2, 28, Belsize Park Gardens, London, NW3 4LH
• Sold May 2015£1,230,500 | 3 Bed Flat43A, Belsize Square, London, NW3 4HN43A, Belsize Square, London, NW3 4HN

Our analysis of the public data ranks Flat C, 23, Belsize Avenue as the 122nd largest and the 68th most expensive of the 446 addresses on Belsize Avenue, London, NW3.

Against the NW3 postcode district average, it is £180k less expensive than the typical property.

• 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

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