Welsh speakers by council, Census 2021
Usual residents of each of Wales's 22 councils by Welsh speakers, Census 2021, from the ONS Census API (its “Number of people aged 3 years and over who can speak Welsh (3 categories)”).
Aged 3 years or over: Cannot speak Welsh, highest: Cardiff
308,483
Census Day, 21 March 2021
Verified against source, 30 October 2026, 11:51 UTCSource: Office for National Statistics (Census 2021). Contains public sector information licensed under the Open Government Licence v3.0.
Data table
22 rows
| Area | Does not apply | Aged 3 years or over: Cannot speak Welsh | Aged 3 years or over: Can speak Welsh |
|---|---|---|---|
| Cardiff W06000015 | 11,068 | 308,483 | 42,757 |
| Swansea W06000011 | 6,601 | 205,903 | 25,986 |
| Rhondda Cynon Taf W06000016 | 7,333 | 201,762 | 28,556 |
| Caerphilly W06000018 | 5,265 | 152,850 | 17,837 |
| Newport W06000022 | 5,715 | 142,283 | 11,594 |
| Flintshire W06000005 | 4,400 | 133,134 | 17,428 |
| Bridgend W06000013 | 4,194 | 128,257 | 13,037 |
| Neath Port Talbot W06000012 | 3,969 | 119,658 | 18,662 |
| Wrexham W06000006 | 4,032 | 115,132 | 15,953 |
| Vale of Glamorgan W06000014 | 3,859 | 113,345 | 14,737 |
| Carmarthenshire W06000010 | 5,178 | 109,881 | 72,838 |
| Powys W06000023 | 3,267 | 108,544 | 21,358 |
| Pembrokeshire W06000009 | 3,152 | 99,580 | 20,626 |
| Monmouthshire W06000021 | 2,267 | 82,835 | 7,852 |
| Conwy W06000003 | 2,936 | 82,805 | 29,000 |
| Torfaen W06000020 | 2,896 | 82,014 | 7,366 |
| Denbighshire W06000004 | 2,755 | 72,116 | 20,946 |
| Blaenau Gwent W06000019 | 2,108 | 60,761 | 4,035 |
| Merthyr Tydfil W06000024 | 1,882 | 51,878 | 5,079 |
| Gwynedd W06000002 | 3,086 | 40,747 | 73,560 |
| Ceredigion W06000008 | 1,564 | 38,233 | 31,678 |
| Isle of Anglesey W06000001 | 1,792 | 29,673 | 37,413 |
Map
Aged 3 years or over: Cannot speak Welsh · 22 areas, each shaded by the fifth of the areas its figure falls in
- 30k to 61k
- 61k to 100k
- 100k to 115k
- 115k to 153k
- 153k to 308k
Boundaries: Council boundaries, May 2026, from the geography spine. Source: Office for National Statistics licensed under the Open Government Licence v.3.0. Contains OS data © Crown copyright and database right 2026.
Source and licence
- Publisher
- Office for National Statistics (Census 2021)
- Check it yourself
- https://www.ons.gov.uk/datasets/create
- Licence
- Open Government Licence v3.0 – Contains public sector information licensed under the Open Government Licence v3.0.
- Retrieved
- 30 October 2026, 11:44 UTC
- Raw files fetched
- https://api.beta.ons.gov.uk/v1/population-types/UR/census-observations?area-type=ltla23&dimensions=welsh_speaking_3_plusSHA-256 cee080c1c77c4d57b61f13978540cfa65f50c630ce1d8964c3665e9952a69492 · 327,799 bytes
- https://api.beta.ons.gov.uk/v1/population-types/UR/dimensions?limit=500SHA-256 456ad46108ca3f46230c3ddad0b5fc65750b9dd557b85a949e0a67d4ca524d12 · 26,631 bytes
Verification
Verified against source, 30 October 2026, 11:51 UTC Run at 30 October 2026, 11:51 UTC; 66 of 66 figures matched the live source.
| Result | Check | Detail |
|---|---|---|
| Pass | Provenance recorded | Office for National Statistics (Census 2021); Open Government Licence v3.0; retrieved 2026-10-30T11:44:25Z; 2 raw file(s) |
| Pass | Raw files match recorded SHA-256 | 2 of 2 files intact |
| Pass | Re-parsing raw files reproduces figures | 66 of 66 figures and the headline reproduced |
| Pass | Figures are finite numbers | 66 figures, 0 invalid |
| Pass | Live source matches every figure | 66 of 66 figures match exactly after downloading 2 source file(s) again (2 byte-identical); the headline matches |
| Pass | The ONS's answer for England and for Wales agrees | in 3 of 3 cells (a category in a nation) the councils sum to the nation's count at https://api.beta.ons.gov.uk/v1/population-types/UR/census-observations?area-type=ctry&dimensions=welsh_speaking_3_plus within twice the square root of the councils summed (0 exactly; the largest gap 0.32 of its limit), the Census's cell-by-cell perturbation |
| Pass | Source page answers | https://www.ons.gov.uk/datasets/create – HTTP 200 |
Notes
- Census Day was the 21st of March 2021. The ONS perturbs every count slightly to protect privacy, each cell on its own, so a council's categories can add up to a total a few people different from one topic to another, and its councils add up to England's and Wales's counts only within a few dozen.
- By council as the ONS's Census API gives them, its lower-tier local authorities of 2023, with Barnsley's and Sheffield's figures under the codes they had until the 1st of April 2025, as the API gives them. Scotland's and Northern Ireland's censuses are separate, so their councils are not here.
- Every council's categories together count all its usual residents, “Does not apply” those the question was not asked of.
- The question was asked in Wales only: the API puts all of England's usual residents under “Does not apply”, so only Wales's 22 councils are here.
- The ONS's description of the topic, “Number of people aged 3 years and over who can speak Welsh (3 categories)”: Classifies people aged 3 years and over living in Wales by whether they can or cannot speak Welsh.