According to data from HM Land Registry, 18, Upper William Street, Llanelli sits on a plot of 141 m².

We have plot size data on 14 out of 17 other houses in the postcode and 18, Upper William Street, Llanelli sits on the 6th largest plot.

18, Upper William Street, Llanelli has an Energy Performance Rating (EPC) of D. This is based on the most recent assessment, dated 11 Mar 2015.

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

According to HM Land Registry, 18, Upper William Street, Llanelli was last sold on 21st October 2003 for £61,750 and was recorded as a freehold house.

The property has had 2 sales since 1995.

• Sold Oct 2003£61,750
• Sold Oct 2003£61,750

According to the Land Registry and our network of Estate Agents, there have been 227 sales of properties similar to 18, Upper William Street, Llanelli within a radius of 460 metres since 2022.

The most recent example is 55, Marble Hall Road, Llanelli, SA15 1NW, a freehold house which sold for £143,000 on the 7th April 2026.

Read more about house prices in SA15.

• Sold Apr 2026£143,000 | 3 Bed House55, Marble Hall Road, Llanelli, SA15 1NW55, Marble Hall Road, Llanelli, SA15 1NW
• Sold Mar 2026£1,100,000 | 3 Bed House16, Als Street, Llanelli, SA15 1SN16, Als Street, Llanelli, SA15 1SN
• Sold Mar 2026£108,000 | 3 Bed House33, Wern Road, Llanelli, SA15 1SP33, Wern Road, Llanelli, SA15 1SP
• Sold Mar 2026£142,000 | 3 Bed House20, Pottery Street, Llanelli, SA15 1TA20, Pottery Street, Llanelli, SA15 1TA
• Sold Feb 2026£145,000 | 3 Bed House69, Pottery Street, Llanelli, SA15 1TA69, Pottery Street, Llanelli, SA15 1TA
• Sold Dec 2025£155,000 | 3 Bed House9, Tunnel Road, Llanelli, SA15 1LE9, Tunnel Road, Llanelli, SA15 1LE
• Sold Oct 2025£105,000 | 3 Bed House32, Marble Hall Road, Llanelli, SA15 1NN32, Marble Hall Road, Llanelli, SA15 1NN
• Sold Oct 2025£150,000 | 3 Bed House48, Upper Robinson Street, Llanelli, SA15 1TR48, Upper Robinson Street, Llanelli, SA15 1TR
• Sold Sep 2025£137,000 | 3 Bed House22, Elizabeth Street, Llanelli, SA15 1TP22, Elizabeth Street, Llanelli, SA15 1TP
• Sold Jul 2025£138,000 | 3 Bed House25, James Street, Llanelli, SA15 1DU25, James Street, Llanelli, SA15 1DU
• Sold Jan 2025£110,000 | 3 Bed House2, Marble Hall Road, Llanelli, SA15 1NN2, Marble Hall Road, Llanelli, SA15 1NN
• Sold Aug 2024£78,000 | 3 Bed House57, Wern Road, Llanelli, SA15 1SP57, Wern Road, Llanelli, SA15 1SP
• Sold Jul 2024£130,000 | 3 Bed House31, Andrew Street, Llanelli, SA15 3YW31, Andrew Street, Llanelli, SA15 3YW
• Sold Apr 2024£95,000 | 3 Bed House15, Wern Road, Llanelli, SA15 1SP15, Wern Road, Llanelli, SA15 1SP
• Sold Mar 2024£120,000 | 3 Bed House53, Andrew Street, Llanelli, SA15 3YW53, Andrew Street, Llanelli, SA15 3YW
• Sold Aug 2022£96,000 | 3 Bed House1A, Marble Hall Road, Llanelli, SA15 1NN1A, Marble Hall Road, Llanelli, SA15 1NN
• Sold Jun 2022£115,000 | 3 Bed House28, James Street, Llanelli, SA15 1DU28, James Street, Llanelli, SA15 1DU
• Sold May 2022£82,500 | 3 Bed House25, Pottery Place, Llanelli, SA15 1ST25, Pottery Place, Llanelli, SA15 1ST
• Sold May 2022£122,000 | 3 Bed House18, James Street, Llanelli, SA15 1DU18, James Street, Llanelli, SA15 1DU
• Sold Feb 2022£100,000 | 3 Bed House5, Als Street, Llanelli, SA15 1SN5, Als Street, Llanelli, SA15 1SN

Upper William Street, Llanelli, SA15 has a total of 17 addresses. According to our analysis of all the public data, 18, Upper William Street, Llanelli is the 6th largest and the 7th most expensive property on the street.

When compared to the postcode district it is £58k less expensive than the average property in SA15.

• Llanelli

  |

  1.0 km away
• Bynea

  |

  4.1 km away
• Llangennech

  |

  5.4 km away

According to data from the Environment Agency, the flood risk in this area is considered to be Very Low.