Carmarthen Population 2026

Carmarthen has a population of 15,854, making it the #765 biggest city in 🇬🇧 United Kingdom, located in Wales. It is about 565× smaller than London, the country's biggest city.

Location of Carmarthen (capital London shown for reference). Boundaries: Natural Earth.

Population (city proper)

15,854

Rank in United Kingdom

#765

Coordinates

51.86°N, 4.31°W

~23 m elevation · Europe/London

Distance to capital (London)

291 km

181 miles, straight line

Other big cities in Wales

City	Population	Rank in United Kingdom
Cardiff	372,089	#10
Swansea	300,352	#21
Newport	161,506	#56
Rhondda	69,506	#157
Wrexham	65,692	#166
Buckley	63,576	#175
Tonypandy	62,545	#182
Barry	54,673	#213

Cities near Carmarthen

Llanelli49,591 people · ~22 km away
Ammanford23,709 people · ~23 km away
Gorseinon20,581 people · ~28 km away
Clydach19,307 people · ~34 km away
Swansea300,352 people · ~36 km away
Neath46,126 people · ~41 km away

FAQ

What is the population of Carmarthen?

Carmarthen has a population of 15,854 (city proper, latest official figure via GeoNames), making it the #765 biggest city in United Kingdom.

What region is Carmarthen in?

Carmarthen is located in Wales, United Kingdom.

Is Carmarthen the capital of United Kingdom?

No, the capital of United Kingdom is London, about 291 km away.

Sources & notes

Population refers to the city proper (municipal boundaries), not the metropolitan area. Source: GeoNames (CC BY 4.0), retrieved 2026-07-07. Country data: UN World Population Prospects 2024.

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