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Census 2011 Ireland and Northern Ireland

The Central Statistics Office (CSO) and the Northern Ireland Statistics and Research Agency (NISRA) today published a special census report titled Census 2011 Ireland and Northern Ireland, the first time comprehensive census results for both parts of the island of Ireland have been brought together in a single report.

Deirdre Cullen, Senior Statistician at the CSO: ‘While the results of the 2011 censuses in Ireland and Northern Ireland have already been extensively published, this report brings these results together for the first time in a single publication. The timing of the censuses, just two weeks apart, on 27 March 2011 in Northern Ireland and 10 April 2011 in Ireland, offers a rare opportunity to present a detailed picture of the populations of both jurisdictions at a single point in time. This report presents analysis across a range of topics in areas such as demographics, households, place of birth, religion, health, housing and travel and has come about as a result of close collaboration between the statistical services in both jurisdictions – the Central Statistics Office (CSO) in Dublin and the Northern Ireland Statistics and Research Agency (NISRA) in Belfast’.

The full report is available on the CSO website at Census 2011 Ireland and Northern Ireland (PDF 5,626KB) ‌ and includes links to the data underlying the charts and tables in the report.

Highlights of the report

Total population

The total population of the island of Ireland in 2011 stood at 6.4 million, comprising 4.6 million persons in Ireland accounting for 72 per cent of the total, and 1.8 million persons in Northern Ireland, representing the remaining 28 per cent. Since 2002 the population in Ireland has grown by 17 per cent, two and a half times the rate of growth in Northern Ireland of 6.9 per cent. While the overall population density for the island as a whole stood at 78 persons per sq. km, the population density of Northern Ireland was 134 persons per sq. km. - double that of Ireland at 67.


In Ireland the median age of the population was 34, the lowest of any EU Member State. The median age in Northern Ireland, while 3 years higher at 37, was also considerably lower than the EU average of 41. Reflecting the older age structure, persons aged 65 and over made up 15 per cent of Northern Ireland’s population, compared with 12 per cent of that of Ireland. Data on this and a range of other statistics are presented in thematic maps in the report to illustrate the differences in the populations in different geographic areas across the island.

Marriage and divorce

Northern Ireland has seen an increase of 20 per cent in the number of single people since the 2001 census, nearly double that of population growth among all persons aged 15 and over (11 per cent), while in Ireland the increase in single people since the 2002 census, at 15 per cent, has been lower than population growth (17 per cent).
There were 56,900 separated and 78,000 divorced persons in Northern Ireland, representing 9.3 per cent of those aged 15 and over, while the comparable figures for Ireland were 87,800 persons divorced and 116,200 separated which together accounted for 5.7 per cent.


The dominant type of households in both jurisdictions comprised married couples with children (of any age), accounting for 32 per cent of households in Ireland and 28 per cent of those in Northern Ireland.
Cohabiting couples were more prevalent in Ireland, accounting for 7.7 per cent of households compared with 5.5 per cent of those in Northern Ireland.


Protestants and Other Christians represented 42 per cent of the population of Northern Ireland while Catholics accounted for 41 per cent, with the remainder made up mainly of those with no religion (10%) or not stated (6.8%). In Ireland, the Catholic religion dominated with 84 per cent of the population while those with no religion made up 5.9 per cent.

Place of birth

In Northern Ireland, 202,000 people, representing 11 per cent of usual residents, were born outside the jurisdiction; 37,900 were born in Ireland, representing almost 1 in 5 of the total. In Ireland, in contrast, the 58,500 people born in Northern Ireland accounted for just 7.6 per cent of the total 766,800 persons born outside Ireland, who in turn represented 17 per cent of the population.


The Wholesale and Retail sector employed the highest proportion of persons of all sectors in both Northern Ireland and Ireland, although rates in Northern Ireland (18 per cent) exceeded those in Ireland (15 per cent). Human health and social work was the second most important sector, with 14 per cent of persons in Northern Ireland and 11 per cent in Ireland, followed by manufacturing, which accounted for 10 and 11 per cent respectively.


Terraced housing accounted for 25 per cent of dwellings in Northern Ireland compared with 17 per cent in Ireland, while the most striking difference between both jurisdictions was for non-private or social rented accommodation, which accounted for 15 per cent of dwellings in Northern Ireland, compared with 8.7 per cent in Ireland. The vacancy rate in Ireland was 15 per cent compared with 6.0 per cent in Northern Ireland.


For the first time, in the 2011 censuses, the place of work or study for persons who travelled from Ireland to Northern Ireland or from Northern Ireland to Ireland was coded to fine geographic level. The results show that a total of 14,800 persons regularly commuted between the two jurisdictions for work or study, with 6,500 travelling to Ireland from Northern Ireland and 8,300 travelling in the other direction.

Deirdre Cullen of the CSO: ‘We trust that this publication will be of value to all government departments and agencies as well as to the cross- border bodies established under the Belfast Agreement. It should also prove valuable to all those who have an interest in the dynamics of population and social change on the island of Ireland’.

This report is published on the CSO and NISRA websites and is also available in hard copy from both organisations.

For copies of the publication:

To view and download the publication, visit the CSO website at Census 2011 Ireland and Northern Ireland (PDF 5,626KB)

For further information contact:

Aileen Healy on (01) 895 1319
Central Statistics Office, Swords Business Campus, Balheary Road, Swords, Co. Dublin.
Census Enquiries: (01) 895 1460
Fax: 01 895 1399
Central Statistics Office                                                                        12 June 2014

– ENDS –