| Postcode | CF45 3DT | 
|---|---|
| Post Town | Mountain Ash | 
| Nearest station | Fernhill (0 km) | 
| Bus stops | Glenboi Primary School (N) Railway Station (SE) Glenboi Cemetery (E) Glenboi Cemetery (NW) Railway Station (NW) Fernhill Estate Middle (NW) | 
| Roads in this postcode | |
| Number of UPRNs | 9 View | 
| Known addresses | 4 Cwm Alarch Close, Mountain Ash | 
| Main property type | Detached | 
| Businesses | 
                        No businesses found
                     | 
| Latitude | 51.683439 | |
|---|---|---|
| Longitude | -3.395265 | |
| Easting | 303636 | |
| Northing | 199220 | |
| Grid reference | ST036992 | |
| UTM reference | 30U 472673 5725904 | |
| what3words | pigment.garden.blip | |
| FixPhrase | crinkle lung structure underhand | |
| Plus code | 9C3RMJM3+9V | |
| Altitude | 146 metres (480 feet) | |
| Sunrise (today) | 7:06 | |
| Sunset (today) | 16:49 | |
| Distance away | ||
| Distance to sea | 28.7 KMs (17.8 miles) | 
| Parish | Mountain Ash West | W04001017 | 
|---|---|---|
| Ward | Mountain Ash | W05001092 | 
| Unitary Authority | Rhondda Cynon Taf | W06000016 | 
| County | Mid Glamorgan | W11000005 | 
| Constituency (2024) | Pontypridd | W07000106 | 
| MP | Alex Davies-Jones | Labour | 
| Police force | South Wales | |
| Water company | Dwr Cymru Welsh Water | |
| NUTS/ITL 3 | Central Valleys and Bridgend | |
| NUTS/ITL 2 | South East Wales | |
| NUTS/ITL 1 | Wales | |
| Country | Wales | W92000004 | 
| Date introduced | September 1991 | 
|---|---|
| Last updated | September 2025 | 
| User type | Small (addresses receive less than 25 items of mail per day) | 
| Quality | Within the building of the matched address closest to the postcode mean | 
| Population (2011) | 12 | |
|---|---|---|
| Households (2011) | 6 | |
| Index of Multiple Deprivation (2019) | Most deprivedLeast deprived | |
| Average household income (2020) | Lowest (£22,200)
                        Highest (£108,100)
                       | |
| Rural/urban (2021) | Urban: Further from a major town or city | |
| Rural/urban (2011) | Urban city and town | |
| Built up area (2024) | Mountain Ash | W45001094 | 
| Census output area (2021) | W00006356 | |
| Census output area (2011) | 6B4 | |
| Lower layer super output area (2021) | Rhondda Cynon Taf 006D | W01001207 | 
| Lower layer super output area (2011) | Rhondda Cynon Taf 006D | W01001207 | 
| Middle layer super output area (2021) | Mountain Ash | W02000257 | 
| Middle layer super output area (2011) | Mountain Ash | W02000257 | 
| Travel to work area | Merthyr Tydfil | W22000029 | 
| Average property price in Cardiff | £221,509 | 
|---|---|
| Annual change | 2.2% | 
| Address | Type | Date | Price | 
|---|---|---|---|
| 4 Cwm Alarch Close, Mountain Ash | Detached (freehold) | Mar 2021 | £165,000 |