# SA31

Postcode district covering Carmarthen and Johnstown, in Carmarthenshire.

SA31 is a postcode district covering Carmarthen and Johnstown, in Carmarthenshire. Median sale price £225,000 in 2025. Recorded crime 155.6 per 1,000 people.

Postcode district. Code SA31. In: [Postcodes](https://openindex.co.uk/postcode) › [SA](https://openindex.co.uk/postcode/sa)

Approximate outline worked out by Open Index from the ONS Postcode Directory: each census output area belongs to the district that holds most of its postcodes. People, homes, recorded crime and broadband add up those output areas. House sales count every sale with an SA31 postcode. [How census figures are added up](https://openindex.co.uk/sources/population)

## Key figures

- **Median sale price: £225,000** (2025). The median price paid for a home in SA31 was £225,000 in 2025. Joint 561st cheapest of 2,235. Source: Worked out by Open Index from HM Land Registry Price Paid Data. Published 28 September 2026. https://openindex.co.uk/postcode/sa31#f-house-sales-median-price
- **Population: 17,582** (2021). SA31 had 17,582 usual residents at the census (ONS Census 2021). 1,143rd least populated of 2,756. Source: Census 2021, England and Wales and Scotland's Census 2022 and Census 2021, Northern Ireland, 2021. Published 21 July 2026. https://openindex.co.uk/postcode/sa31#f-population
- **People in radon Affected Area squares: 100%** (2022). About 100% of people in SA31 live in a 1 km square that the radon atlas marks as a radon Affected Area. UK 44%. Source: Worked out by Open Index from the UKHSA and BGS radon atlas and census output areas. Published 1 December 2022. https://openindex.co.uk/postcode/sa31#f-radon-affected-share
- **Gigabit broadband coverage: 78.3%** (January 2026). In SA31, 78.3% of homes and businesses could get gigabit-capable broadband in January 2026 (Ofcom). UK 87.8%. Source: Connected Nations (Ofcom), January 2026. Published 13 May 2026. https://openindex.co.uk/postcode/sa31#f-gigabit-coverage

## On the map

- [Radon Affected Area by postcode district](https://openindex.co.uk/map/radon-affected-areas?place=SA31) (Worked out by Open Index · 2022): About 100% of people in SA31 live in a 1 km square that the radon atlas marks as a radon Affected Area.
- [Sales per year by postcode district](https://openindex.co.uk/map/house-sales-per-year?place=SA31) (Worked out by Open Index · 2025): 248 homes were sold in SA31 in 2025.
- [Crime and ASB by postcode district](https://openindex.co.uk/map/recorded-crime?place=SA31) (Police recorded crime and outcomes (data.police.uk) · August 2026): Crime and anti-social behaviour for SA31.
- [Population by postcode district](https://openindex.co.uk/map/population?place=SA31) (Census 2021, England and Wales): SA31 had 17,582 usual residents at the census.

## How SA31 compares

Each postcode district against every other postcode district the measure covers.

| Measure | SA31 | Rank | Compared with |
| --- | --- | --- | --- |
| Median sale price | £225,000 | joint 24th most expensive | 49 postcode districts, SA · 2025 |
| Population | 17,582 | 16th most populated | 52 postcode districts, SA · 2021 |
| People in radon Affected Area squares | 100% | joint most people in radon Affected Areas | 52 postcode districts, SA · 2022 |
| Gigabit broadband coverage | 78.3% | 25th highest | 52 postcode districts, SA · Jan 2026 |

## Is SA31 safe? What police records show

In the 12 months to August 2026, police recorded crimes and anti-social behaviour in SA31 at a rate of 155.6 per 1,000 people.
That compares with 86.6 per 1,000 people across the SA postcode area.
In August 2026 alone, 233 cases of crime and anti-social behaviour were recorded in SA31.
In the 12 months to August 2026, the most common types were violence and sexual offences (1,252), other crime (483) and shoplifting (284).
A year earlier, the recorded crime rate in SA31 was 150.3 per 1,000 people.
Worked out by Open Index from police.uk crime records and ONS and NISRA population estimates.
Rates are per resident, so places that many people work in or visit, such as Westminster, the City of London and other city centres, have far higher rates than their residents alone would suggest.

## Deprivation in SA31, neighbourhood by neighbourhood

- Deprivation is ranked by neighbourhood, so SA31 has no single figure. Of its 11 neighbourhoods with a rank:
- Decile 2: 1 neighbourhood
- Decile 3: 2 neighbourhoods
- Decile 5: 2 neighbourhoods
- Decile 6: 1 neighbourhood
- Decile 7: 1 neighbourhood
- Decile 8: 3 neighbourhoods
- Decile 10 (Wales’s least deprived 10%): 1 neighbourhood

Source: Welsh Index of Multiple Deprivation 2025. Decile 1 is the most deprived tenth of neighbourhoods in Wales.

## Neighbourhoods in SA31

| Area | People (census) | Recorded crime per 1,000 | Deprivation decile | Gigabit broadband |
| --- | --- | --- | --- | --- |
| [Carmarthenshire 006A](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000643) | 1,671 | 92.1 per 1,000 | 5 | 92.0% |
| [Carmarthenshire 006B](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000644) | 1,880 | 82.5 per 1,000 | 8 | 82.5% |
| [Carmarthenshire 006C](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000645) | 1,970 | 81.5 per 1,000 | 7 | 91.2% |
| [Carmarthenshire 007A](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000637) | 1,388 | 105.1 per 1,000 | 3 | 94.2% |
| [Carmarthenshire 007B](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000638) | 1,150 | 151.0 per 1,000 | 2 | 86.7% |
| [Carmarthenshire 007C](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000639) | 1,521 | 134.4 per 1,000 | 6 | 91.6% |
| [Carmarthenshire 007D](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000640) | 1,229 | 122.3 per 1,000 | 10 | 60.7% |
| [Carmarthenshire 008A](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000641) | 2,063 | 443.5 per 1,000 | 3 | 70.5% |
| [Carmarthenshire 008B](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000642) | 1,761 | 129.4 per 1,000 | 8 | 85.1% |
| [Carmarthenshire 008C](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000693) | 1,128 | 163.6 per 1,000 | 5 | 55.9% |
| [Carmarthenshire 008D](https://openindex.co.uk/carmarthenshire/neighbourhood/w01000694) | 1,499 | 140.0 per 1,000 | 8 | 45.8% |

## Your MP

- [Caerfyrddin](https://openindex.co.uk/constituency/caerfyrddin): Ann Davies (Plaid Cymru), MP since July 2024. 98% of the people here.
- [Llanelli](https://openindex.co.uk/constituency/llanelli): Dame Nia Griffith (Labour), MP since July 2024. 2.1% of the people here.

As of 18 October 2026. Contains Parliamentary information licensed under the Open Parliament Licence v3.0. Source: UK Parliament, Members API.

## Middle areas in SA31

[Carmarthen North](https://openindex.co.uk/carmarthenshire/carmarthen-north), [Carmarthen South & Llangynnwr](https://openindex.co.uk/carmarthenshire/carmarthen-south-and-llangynnwr), [Carmarthen West & Cynwyl Elfed](https://openindex.co.uk/carmarthenshire/carmarthen-west-and-cynwyl-elfed)

## Postcode sectors in SA31

[SA31 1 (208 postcodes)](https://openindex.co.uk/postcode/sa31-1), [SA31 2 (150 postcodes)](https://openindex.co.uk/postcode/sa31-2), [SA31 3 (203 postcodes)](https://openindex.co.uk/postcode/sa31-3), [SA31 9 (19 postcodes)](https://openindex.co.uk/postcode/sa31-9)

## Council

[Carmarthenshire](https://openindex.co.uk/carmarthenshire)

## Towns in SA31

[Carmarthen](https://openindex.co.uk/town/carmarthen)

## Postcode districts next to SA31

[SA17](https://openindex.co.uk/postcode/sa17), [SA32](https://openindex.co.uk/postcode/sa32), [SA33](https://openindex.co.uk/postcode/sa33)

## Nearest rail stations

[Carmarthen (2.4 km from the middle)](https://openindex.co.uk/map/rail-stations?around=-4.3060,51.8533)

## More in the SA postcode area

[All SA postcode districts](https://openindex.co.uk/postcode/sa), [Every UK postcode area](https://openindex.co.uk/postcode)

## SA31 in brief

SA31 is a postcode district covering Carmarthen and Johnstown, in Carmarthenshire.
About 17,993 people lived in SA31 in mid-2024 (worked out by Open Index from ONS small-area estimates); the median price paid for a home was £225,000 in 2025 across 248 sales (HM Land Registry) and police recorded crimes and anti-social behaviour at a rate of 155.6 per 1,000 people in the 12 months to August 2026 (police.uk).
The median price paid for a home in SA31 was £225,000 in 2025.
SA31 had 17,582 usual residents at the census.
About 100% of people in SA31 live in a 1 km square that the radon atlas marks as a radon Affected Area.
In SA31, 78.3% of homes and businesses could get gigabit-capable broadband in January 2026.

## About

- Type: Postcode district
- Code: SA31
- Postcode area: [SA](https://openindex.co.uk/postcode/sa)
- Constituency: [Caerfyrddin †](https://openindex.co.uk/constituency/caerfyrddin)
- Council: [Carmarthenshire †](https://openindex.co.uk/carmarthenshire)
- Area: 34.29 km²
- People, mid-2024: 17,993*
- Neighbourhoods: 11
- Output areas: 59

* People: worked out by Open Index from neighbourhood estimates, shared out by where people lived at the census (by area in Northern Ireland). This area's edges do not follow neighbourhood edges, so the figure is close but not exact.
† Best fit: the constituency, council and nation this postcode district mostly lies in. Its edges do not follow theirs.

## Next door

[SA32](https://openindex.co.uk/postcode/sa32), [SA33](https://openindex.co.uk/postcode/sa33), [SA17](https://openindex.co.uk/postcode/sa17)

## Latest updates for SA31

- August 2026 house prices published: HM Land Registry and partners · Oct 2026.
- September 2026 rent published: ONS private rents · Oct 2026.
- Dental practices updated: NHS England · Oct 2026.
- Schools updated: Ofsted · Oct 2026.

The same figures as JSON: https://openindex.co.uk/v1/places/SA31

## How to cite

Source: Open Index, openindex.co.uk. Link to this page, https://openindex.co.uk/postcode/sa31, or to one figure with its anchor, https://openindex.co.uk/postcode/sa31#f-house-sales-median-price.

Open Index's own text and the figures it works out are licensed under CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Source data keeps its publishers' licences, named with each figure. Give each figure's period and source with it.

Snapshot 2026.10.9. The HTML page: https://openindex.co.uk/postcode/sa31