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Census shows population of Wales is more than three million

Released: 16 July 2012 Download PDF (88.5 Kb)

The population of Wales on census day (27 March 2011) was 3.06 million – an increase of 153,000 (5 per cent) in the past 10 years, from 2.91 million in 2001. The Office for National Statistics (ONS) published the first results from the 2011 Census today.

The growth in Wales was the largest in any 10 year period between censuses since 1921. Around 90 per cent of the growth was due to migration, including people moving to Wales from elsewhere in the UK as well as international migration.

Jil Matheson, National Statistician, said:

"I'd like to thank everyone in Wales for their support. The 2011 Census has been a resounding success and I am proud of the incredible effort that has been put in. It is a rich source of information about the population and its characteristics. Across England and Wales around 19 out of 20 people responded and we have excellent statistical methods for ensuring we have a complete estimate of the whole population. These statistics will provide valuable information for planners, policy-makers and the public for years to come."

Of the local authorities in Wales, Cardiff had both the highest population, at 346,000 people, and the largest growth in population with an increase of 36,000 (12 per cent) from 2001. It was also the most densely populated, with 2,500 people per square kilometre, the equivalent of around 25 people on a rugby pitch.

Most authorities in Wales saw an increase in population since 2001, although there was a small decrease (0.3 per cent) in Blaenau Gwent. Across all of England and Wales 17 local authorities saw a decline in population. 

The Welsh unitary authority with the largest proportion of people aged 65 and over was Conwy with 25 per cent, and the smallest proportion was in Cardiff (13 per cent). Wales also has a higher proportion of 65-year-olds than nearly all the regions of England. 

Across England and Wales there was a significant increase in the number of under-five-year-olds. In Wales there were 11,000 more under-five-year-olds in 2011 than in 2001, an increase of 7 per cent. Wrexham had the largest proportion in this age group with 7 per cent, while the smallest proportion was in Ceredigion with 5 per cent. By comparison, the number of under fives in England increased by 13 per cent, approximately twice as quickly as in Wales.

The smallest average household size was in Conwy with 2.2 people. In general there was little variation in average household size across Wales. 

Compared with England, population growth between 2001- 2011 was slower in Wales. In the same period the population of England rose by 3.6 million (7 per cent).

Glen Watson, Census Director said:

 "The whole operation has worked well. We met our targets both for response and quality. We’ve had fantastic support from the public, and also from voluntary groups, community groups and local authorities throughout England and Wales. I’d like to say a big thank you to everyone involved, including the 35,000 people who worked on the data collection and helped to make the census a success."

Read the full reports:

Local Authorities in Wales ranked by population size in 2011 Census

Local Authority 2011 population 2001 population Change 2001-2011 (per cent)
Cardiff 346,100 310,100 11.6
Swansea 239,000 223,500 6.9
Rhondda Cynon Taf 234,400 231,900 1.1
Carmarthenshire 183,800 173,700 5.8
Caerphilly 178,800 169,500 5.5
Flintshire 152,500 148,600 2.6
Newport 145,700 137,600 5.9
Neath Port Talbot 139,800 134,400 4
Bridgend 139,200 128,700 8.2
Wrexham 134,800 128,500 4.9
Powys 133,000 126,400 5.2
The Vale of Glamorgan 126,300 119,300 5.9
Pembrokeshire 122,400 113,100 8.2
Gwynedd 121,900 116,800 4.4
Conwy 115,200 109,700 5
Denbighshire 93,700 93,100 0.6
Monmouthshire 91,300 85,000 7.4
Torfaen 91,100 90,900 0.2
Ceredigion 75,900 75,400 0.7
Blaenau Gwent 69,800 70,000 -0.3
Isle of Anglesey 69,700 67,800 2.8
Merthyr Tydfil 58,800 56,200 4.6

Table source: Office for National Statistics

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Background notes

  1. The census provides the most accurate estimate possible for the population of England and Wales and has been carried out every 10 years since 1801, apart from 1941, by the Office for National Statistics (ONS). The information provided to ONS is used solely for the census, is anonymised and protected for 100 years. Census day was on 27 March 2011. All census population numbers refer to that day.
  2. Government uses the census statistics to allocate funding for services such as education, transport and health. Policy makers in central and local government use the census to identify the needs of different communities and they are also used by commercial enterprises. It also provides the benchmark for future population estimates and for sample surveys.
  3. People living in Wales received both a Welsh and English version of the questionnaire and each included an extra question about the Welsh language.
  4. For the first time every census questionnaire form could be filled out and returned on-line. 8,900 returns were completed using the Welsh language version of the online questionnaire.
  5. The 2011 Census figures will be used to base the 2011 population mid-year estimates which are due for release in September 2012. In due course the mid-year population estimates for 2002-2010 will be rebased.
  6. National statistics are produced to high professional standards set out in the National Statistics Code of Practice. They undergo regular quality assurance reviews to ensure that they meet customer needs. They are produced free from any political interference.
  7. The second release, due between November 2012 and February 2013, will feature more detailed statistics including national identity, ethnicity, Welsh language, marital and civil partnership status, and religion.
  8. For the latest on census, follow us on Twitter: @2011censusinfo.
  9. Some facts about the collection of census data across England and Wales:
    • the 26 million 32-page (16 sheets of paper) questionnaires sent to households in England and Wales were printed at the rate of eight questionnaires per second
    • stacked up, they would be 200 times the height of The Shard
    • questionnaires were processed at a rate of 170,000 per day
    • questionnaires were printed on paper from sustainable sources and 1,700 tonnes were destroyed and recycled after processing

  10. Details of the policy governing the release of new data are available by visiting or from the Media Relations Office email:

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