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Census 2021 demography and international migration statistics for Wales

Today the Office for National Statistics (ONS) has published the next phase of Census 2021 outputs for England and Wales where we look at topics including migration, country of birth and household size and structure.

The number of residents of Wales born outside of the UK has shown a small increase in the decade since the last census.

New data from Census 2021 show 215,000 out of 3.1 million residents (1 in 14) in Wales were born outside the UK. In 2011, this was around 1 in 18 residents. It also compares with 1 in 6 across England and Wales, as a whole, in 2021.

Nearly 25,000 (0.8% of the population of Wales) were born in Poland (up from 18,000 in 2011) and 13,400 (0.4%) were born in India (up from 11,900 in 2011).

When looking across England and Wales, Wales had three local authorities (LAs) among the 10 with the lowest proportion of non-UK born residents: Caerphilly (2.9%), Blaenau Gwent (3.2%) and Isle of Anglesey (3.3%). 

Commenting on today's numbers, Census Deputy Director Jon Wroth-Smith said:

"The census paints a picture of how the make-up of the population has changed in the past decade. That decade, of course, saw us leave the EU as well as live with the pandemic.

"While these events may have had an impact on people's decisions or ability to migrate or travel at a given time, the census tells us about the change over the whole decade – who was living here in March 2021, compared with March 2011. We can see, in Wales, the non-UK born population has increased slightly, with Poland and India being the most common non-UK country of birth. The Welsh local authority with the highest proportion of non-UK born residents was Cardiff, where around one in six residents were born overseas." 

Characteristics of the population

Today's release Household and resident characteristics, England and Wales: Census 2021 also sheds light on the characteristics of people living in Wales and shows a similar picture to 2011.

In Wales, there were 2.3 people living in each household on average. Cardiff and Newport both had the highest average household sizes (2.4 people), while Conwy had the lowest (2.2 people). 

The LAs with the highest proportion of one-person households were Gwynedd (34.6%), Swansea (34.4%) and Conwy (34.3%). The LAs with the highest proportion of five-person households were Cardiff (4.6%), Newport (4.4%) and Gwynedd (4.2%). 

Cardiff had the highest proportion of single people in Wales with 48.6%. Monmouthshire had the lowest with 28.9%. This compares with 37.2% nationally across Wales.

The highest proportion of married people (opposite-sex and same-sex marriages) was in Monmouthshire with 51.1%. The lowest proportion was in Cardiff with 36.6%. This compares with 43.7% across Wales. 

How old is your town?

The median age of the population in Wales was 42 years, up from 41 in 2011. But the picture presented today in Population and household estimates, England and Wales: Census 2021, unrounded data varies between urban and rural areas, and those areas with large student populations. 

Across Wales, the LAs with the highest median age were Powys (50 years) and Monmouthshire and Conwy (both 49 years).

The LAs with the lowest median age were Cardiff (34 years), followed by Newport (38 years) and Merthyr Tydfil (40 years).

More information

Today, the ONS has made Demography and Migration univariate data available via our website. The data are provided as downloadable Excel spreadsheets in the first instance, with application programming interfaces (APIs) available soon via the NOMIS and ONS websites. To accompany these data, we have a range of explanatory and exploratory products to illustrate the richness of these data.

The Census 2021 dictionary provides detailed information about variables, definitions and classifications to help when using Census 2021 data.

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