20, William Street, Caernarfon occupies a 46 m² plot as recorded by HM Land Registry.

Of the 39 other houses in this postcode, 38 have recorded plot sizes, and this one ranks as the 35th largest.

20, William Street, Caernarfon has an Energy Performance Rating (EPC) of D. This is based on the most recent assessment, dated 12 Aug 2016.

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

20, William Street, Caernarfon last changed hands on 23rd May 2022, selling for £107,500. The transaction was logged as a freehold house by HM Land Registry.

In total it has sold 3 times since 1995.

The market for similar properties has risen by 19.3% since May 2022.

• Sold May 2022£107,500
• Sold Sep 2002£48,500
• Sold Feb 1997£34,950

Land Registry records and our Estate Agent network show 65 sales of comparable properties within 510 metres of 20, William Street, Caernarfon since 2011.

Most recently, 47, Assheton Terrace, Caernarfon, LL55 2LD, a freehold house, sold at £146,250 on the 20th February 2026.

Read more about house prices in LL55.

• Sold Feb 2026£146,250 | 3 Bed House47, Assheton Terrace, Caernarfon, LL55 2LD47, Assheton Terrace, Caernarfon, LL55 2LD
• Sold Feb 2026£124,000 | 3 Bed House41, Assheton Terrace, Caernarfon, LL55 2LD41, Assheton Terrace, Caernarfon, LL55 2LD
• Sold Sep 2025£120,000 | 3 Bed House4, Cadnant Road, Caernarfon, LL55 1NA4, Cadnant Road, Caernarfon, LL55 1NA
• Sold Aug 2025£92,500 | 3 Bed House18, New Street, Caernarfon, LL55 2PU18, New Street, Caernarfon, LL55 2PU
• Sold Jun 2025£106,000 | 3 Bed House7, Tithebarn Street, Caernarfon, LL55 2RF7, Tithebarn Street, Caernarfon, LL55 2RF
• Sold Mar 2025£95,000 | 3 Bed House3, Cadnant Road, Caernarfon, LL55 1NA3, Cadnant Road, Caernarfon, LL55 1NA
• Sold Jan 2025£90,000 | 3 Bed House34, William Street, Caernarfon, LL55 1ND34, William Street, Caernarfon, LL55 1ND
• Sold Nov 2024£150,000 | 3 Bed House12, Holywell Terrace, Caernarfon, LL55 2AP12, Holywell Terrace, Caernarfon, LL55 2AP
• Sold Oct 2024£90,000 | 3 Bed House28, William Street, Caernarfon, LL55 1ND28, William Street, Caernarfon, LL55 1ND
• Sold Jul 2024£111,000 | 3 Bed House37, William Street, Caernarfon, LL55 1ND37, William Street, Caernarfon, LL55 1ND
• Sold Oct 2022£110,000 | 3 Bed House39, William Street, Caernarfon, LL55 1ND39, William Street, Caernarfon, LL55 1ND
• Sold Jun 2022£135,000 | 3 Bed House23, New Street, Caernarfon, LL55 2PU23, New Street, Caernarfon, LL55 2PU
• Sold Mar 2021£100,000 | 3 Bed House56, Chapel Street, Caernarfon, LL55 2PS56, Chapel Street, Caernarfon, LL55 2PS
• Sold Jun 2020£95,000 | 3 Bed House14, William Street, Caernarfon, LL55 1ND14, William Street, Caernarfon, LL55 1ND
• Sold Jul 2019£95,000 | 3 Bed House32, William Street, Caernarfon, LL55 1ND32, William Street, Caernarfon, LL55 1ND
• Sold Nov 2017£50,000 | 3 Bed House7, New Street, Caernarfon, LL55 2PU7, New Street, Caernarfon, LL55 2PU
• Sold Oct 2017£63,000 | 3 Bed House9, New Street, Caernarfon, LL55 2PU9, New Street, Caernarfon, LL55 2PU
• Sold Mar 2015£98,500 | 3 Bed House15, William Street, Caernarfon, LL55 1ND15, William Street, Caernarfon, LL55 1ND
• Sold Jan 2013£88,000 | 3 Bed House17, William Street, Caernarfon, LL55 1ND17, William Street, Caernarfon, LL55 1ND
• Sold Sep 2011£100,000 | 3 Bed House25, William Street, Caernarfon, LL55 1ND25, William Street, Caernarfon, LL55 1ND

Our analysis of the public data ranks 20, William Street, Caernarfon as the 16th largest and the 17th most expensive of the 39 addresses on William Street, Caernarfon, LL55.

Against the LL55 postcode district average, it is £107k less expensive than the typical property.

• Llanfairpwll

  |

  9.8 km away
• Bodorgan

  |

  12.2 km away
• Bangor (Gwynedd)

  |

  12.7 km away

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