HM Land Registry records the plot of land for 21, Flask Walk as measuring 107 m².

That makes it the 13th largest plot in the postcode, where all 15 other houses have recorded plot data.

21, Flask Walk has an Energy Performance Rating (EPC) of C. This is based on the most recent assessment, dated 07 Jan 2026.

The property is connected to mains gas and has mostly double glazing. It is heated using a boiler and radiators (mains gas).

The most recent sale of 21, Flask Walk completed on 15th March 1999 at £499,999 and was recorded by HM Land Registry as a freehold house.

Since 1995 this is the property's only sale.

• Sold Mar 1999£499,999

Since 2011 32 properties similar to 21, Flask Walk have sold within a radius of 300 metres, per the Land Registry and our network of Estate Agents.

The latest, on the 5th June 2026, was 24, Flask Walk, London, NW3 1HE, a freehold house which sold for £1,800,000.

Read more about house prices in NW3.

• Sold Jun 2026£1,800,000 | 3 Bed House24, Flask Walk, London, NW3 1HE24, Flask Walk, London, NW3 1HE
• Sold Dec 2025£2,185,000 | 4 Bed House17, The Mount, London, NW3 6SZ17, The Mount, London, NW3 6SZ
• Sold Nov 2025£1,500,000 | 4 Bed HouseSide Door, 16, Flask Walk, London, NW3 1HESide Door, 16, Flask Walk, London, NW3 1HE
• Sold Mar 2023£2,300,000 | 3 Bed House19, Holly Walk, London, NW3 6RA19, Holly Walk, London, NW3 6RA
• Sold Oct 2022£1,900,000 | 3 Bed House22, Flask Walk, London, NW3 1HE22, Flask Walk, London, NW3 1HE
• Sold Aug 2022£2,550,000 | 4 Bed House61, New End, London, NW3 1HY61, New End, London, NW3 1HY
• Sold Jul 2022£2,600,000 | 4 Bed House14, The Mount, London, NW3 6SZ14, The Mount, London, NW3 6SZ
• Sold Jun 2022£1,830,000 | 4 Bed House39, Flask Walk, London, NW3 1HH39, Flask Walk, London, NW3 1HH
• Sold Sep 2021£2,500,000 | 4 Bed House35, Flask Walk, London, NW3 1HH35, Flask Walk, London, NW3 1HH
• Sold Jan 2021£1,595,000 | 3 Bed House47, Flask Walk, London, NW3 1HH47, Flask Walk, London, NW3 1HH
• Sold Oct 2020£2,400,000 | 4 Bed House2, The Mount, London, NW3 6SZ2, The Mount, London, NW3 6SZ
• Sold Sep 2020£1,640,000 | 3 Bed House14, Back Lane, London, NW3 1HL14, Back Lane, London, NW3 1HL
• Sold Feb 2020£1,300,000 | 4 Bed House8, Benhams Place, London, NW3 6QX8, Benhams Place, London, NW3 6QX
• Sold Jun 2018£2,850,000 | 4 Bed House5, Back Lane, London, NW3 1HL5, Back Lane, London, NW3 1HL
• Sold Aug 2015£2,000,000 | 3 Bed House2, Martys Yard, London, NW3 1QW2, Martys Yard, London, NW3 1QW
• Sold Jul 2015£2,025,000 | 4 Bed House38, New End Square, London, NW3 1LS38, New End Square, London, NW3 1LS
• Sold Jan 2015£1,350,000 | 4 Bed House7, Benhams Place, London, NW3 6QX7, Benhams Place, London, NW3 6QX
• Sold May 2014£1,770,000 | 4 Bed House6, Perrins Court, London, NW3 1QS6, Perrins Court, London, NW3 1QS
• Sold Dec 2011£1,600,000 | 3 Bed House7, Back Lane, London, NW3 1HL7, Back Lane, London, NW3 1HL
• Sold Jan 2011£1,495,000 | 4 Bed House18, Flask Walk, London, NW3 1HE18, Flask Walk, London, NW3 1HE

Of the 81 addresses on Flask Walk, London, NW3, 21, Flask Walk comes out as the 33rd largest and the 24th most expensive in our analysis of the public data.

It is also £727k more expensive than the average property across the NW3 district.

• New End Primary School

  100 m away
• Hampstead Parochial Church of England Primary School

  200 m away
• Christ Church Primary School, Hampstead

  300 m away

• The UCL Academy

  1.8 km away
• William Ellis School

  1.8 km away
• Parliament Hill School

  1.9 km away

• Hampstead

  |

  100 m away
• Hampstead Heath

  |

  800 m away
• Finchley Road & Frognal

  |

  900 m away

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