15, William Street, Caernarfon occupies a 54 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 33rd largest.

15, William Street, Caernarfon has an Energy Performance Rating (EPC) of D. This is based on the most recent assessment, dated 05 Dec 2025.

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

15, William Street, Caernarfon last changed hands on 21st February 2003, selling for £59,500. The transaction was logged as a freehold house by HM Land Registry.

That is its only recorded sale since 1995.

• Sold Feb 2003£59,500

Land Registry records and our Estate Agent network show 70 sales of comparable properties within 510 metres of 15, William Street, Caernarfon since 2016.

Most recently, 7, Hendre Street, Caernarfon, LL55 2HY, a freehold house, sold at £99,000 on the 3rd October 2025.

Read more about house prices in LL55.

• Sold Oct 2025£99,000 | 2 Bed House7, Hendre Street, Caernarfon, LL55 2HY7, Hendre Street, Caernarfon, LL55 2HY
• 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 May 2025£105,000 | 2 Bed House34, New Street, Caernarfon, LL55 2PU34, New Street, Caernarfon, LL55 2PU
• Sold Feb 2025£115,000 | 2 Bed House24, South Penrallt, Caernarfon, LL55 1NS24, South Penrallt, Caernarfon, LL55 1NS
• 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 Jul 2024£111,000 | 3 Bed House37, William Street, Caernarfon, LL55 1ND37, William Street, Caernarfon, LL55 1ND
• Sold Jun 2024£111,500 | 2 Bed House13, Assheton Terrace, Caernarfon, LL55 2LD13, Assheton Terrace, Caernarfon, LL55 2LD
• Sold Sep 2023£118,000 | 2 Bed House4, William Street, Caernarfon, LL55 1ND4, William Street, Caernarfon, LL55 1ND
• Sold Feb 2023£137,500 | 2 Bed House37, South Penrallt, Caernarfon, LL55 1NS37, South Penrallt, Caernarfon, LL55 1NS
• Sold Oct 2022£110,000 | 3 Bed House39, William Street, Caernarfon, LL55 1ND39, William Street, Caernarfon, LL55 1ND
• Sold Aug 2022£70,000 | 2 Bed House4, Pool Street, Caernarfon, LL55 2AB4, Pool Street, Caernarfon, LL55 2AB
• Sold Jun 2022£134,000 | 2 Bed House40, William Street, Caernarfon, LL55 1ND40, William Street, Caernarfon, LL55 1ND
• Sold May 2022£107,500 | 3 Bed House20, William Street, Caernarfon, LL55 1ND20, William Street, Caernarfon, LL55 1ND
• Sold Aug 2021£102,000 | 2 Bed House29, William Street, Caernarfon, LL55 1ND29, William Street, Caernarfon, LL55 1ND
• Sold Dec 2020£90,000 | 2 Bed House21, William Street, Caernarfon, LL55 1ND21, William Street, Caernarfon, LL55 1ND
• 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 May 2016£111,000 | 2 Bed House2, William Street, Caernarfon, LL55 1ND2, William Street, Caernarfon, LL55 1ND

Our analysis of the public data ranks 15, William Street, Caernarfon as the 22nd largest and the 23rd most expensive of the 39 addresses on William Street, Caernarfon, LL55.

Against the LL55 postcode district average, it is £112k 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.