List of Welsh principal areas by population
This is a list of principal areas of Wales ordered by population.
The figures are estimates for from the Office for National Statistics.
Rank | District | Population | Population density/km² | Style |
| Cardiff | | | City and county |
| Swansea | | | City and county |
| Rhondda Cynon Taf | | | County borough |
| Carmarthenshire | | | County |
| Caerphilly | | | County borough |
| Flintshire | | | County |
| Newport | | | City |
| Bridgend | | | County borough |
| Neath Port Talbot | | | County borough |
| Wrexham | | | County borough |
| Powys | | | County |
| Vale of Glamorgan | | | County borough |
| Pembrokeshire | | | County |
| Gwynedd | | | County |
| Conwy | | | County borough |
| Denbighshire | | | County |
| Monmouthshire | | | County |
| Torfaen | | | County borough |
| Ceredigion | | | County |
| Isle of Anglesey | | | County |
| Blaenau Gwent | | | County borough |
| Merthyr Tydfil | | | County borough |