National and subnational mid-year population estimates for the UK and its constituent countries by administrative area, age and sex (including components of population change, median age and population density).

Description of Data Population estimates for the 3,780 Data Zones in Northern Ireland were published on 29th May 2025. Time Period Estimates are provided for mid-2021 to mid-2023. Notes: 1. Estimated populations are given as of 30th June for the year noted, rounded to the nearest person. 2. Rounding for estimates at this geographic level is independent. As such, figures may not add to higher geography totals. Methodology The population estimates for small geographical areas are created from an average of two statistical methods: the ratio change and cohort-component methods. The ratio change method applies the change in secondary (typically administrative) data sources to Census estimates. The 2023 small geographical area estimates use a single statistical dataset which has been created by amalgamating a series of different administrative data sources. This statistical dataset is a de-duplicated admin based estimate for the usually resident population of NI. The cohort-component method updates the Census estimates by ‘ageing on’ populations and applying information on births, deaths and migration. An average of both methods is taken and constrained to the published population figures. Further information is available at: NISRA 2023 Mid-year Population Estimates webpage Geographic Referencing Population Estimates are based on a large number of secondary datasets. Where the full address was available, the Pointer Address database was used to allocate a unique property reference number (UPRN) and geo-spatial co-ordinates to each home address. These can then be used to map the address to particular geographies. Where it was not possible to assign a unique property reference number to an address using the Pointer database, or where the secondary dataset contained only postcode information, the Central Postcode Directory was used to map home address postcodes to higher geographies. A small proportion of records with unknown geography were apportioned based on the spatial characteristics of known records. Further Information The next estimates of the population for Northern Ireland will be released later in 2025. Contact: NISRA Customer Services 02890 255156 census@nisra.gov.uk Responsible Statistician: Shauna Dunlop

This dataset provides Census 2021 estimates for the number of usual residents in Northern Ireland. The dataset also shows the population density, as well as the size of the geographical area. The estimates and area boundaries are as at census day, 21 March 2021.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

To find out how Data Zones and Super Data Zones have been developed, and how other Northern Ireland geographies can be approximated, please read the notes here

The quality assurance report can be found here

The National Population Database (NPD) for Northern Ireland is a point-based Geographical Information System (GIS) dataset that combines locational information from Ordnance Survey Northern Ireland (OSNI) with population information about those locations, mainly sourced from Northern Irish government statistics. The points represent individual buildings allowing the NPD NI to provide detailed local analysis for anywhere in Northern Ireland.

The Health and Safety Laboratory (HSL) working with Staffordshire University originally created the NPD for Great Britain in 2004 to help its parent organisation, the Health and Safety Executive (HSE), assess the risks to society of major hazard sites e.g. oil refineries, chemical works and gas holders. Of particular interest to HSE were ‘sensitive’ populations e.g. schools and hospitals where the people at those locations may be more vulnerable to harm and potentially harder to evacuate in an emergency. The data for the NPD NI includes residential, schools and colleges, hospitals and workplace layers.

The NPD NI was created using various datasets from OSNI and government organisations and contains other intellectual property so is only available under a license and for a fee. Please contact the HSL GIS team if you would like to discuss gaining access to the sample or full dataset.

Population estimates relate to the population as of 30th June each year, and therefore are often referred to as mid-year estimates. These population estimates provide population totals for the 4,537 Small Areas in Northern Ireland and therefore can be used as building blocks for population estimates for higher level geographies.

Report describing the quality of mid-year population estimates in Northern Ireland using comparator data sources and demographic analysis Source agency: Northern Ireland Statistics and Research Agency Designation: Supporting material Language: English Alternative title: Northern Ireland Mid Year Population Estimates Quality Report

These statistics contain the first results from Census 2021, and provide estimates of the Northern Ireland population by five-year age band and sex, residence type, and the household count with average household size.

Estimates in this release were published in rounded form.

Description of Data Notes: 1. Net Migration is the difference between inflows and outflows. Inflows = people coming to Northern Ireland to live Outflows = people leaving Northern Ireland to live elsewhere 2. In general the precision of the migration estimates could be considered to be no better than to the nearest 100. 3. The estimates are produced using a variety of data sources and statistical models. Therefore small estimates should not be taken to refer to particular individuals. 4. The migration element of the components of change have been largely derived from a data source which is known to be deficient in recording young adult males and outflows from Northern Ireland. Therefore the estimates are subject to adjustment to account for this and, while deemed acceptable for their use, will not provide definitive numbers of the population in the reported groups/areas. Further information is available in the Limitations section of the statistical bulletin: NISRA 2023 Mid-year Population Estimates webpage Time Period Estimates are provided for mid-2002 to mid-2023. Methodology The cohort-component method was used to create the population estimates for 2022. This method updates the Census estimates by 'ageing on' populations and applying information on births, deaths and migration. Further information is available at: NISRA 2023 Mid-year Population Estimates webpage Geographic Referencing Population Estimates are based on a large number of secondary datasets. Where the full address was available, the Pointer Address database was used to allocate a unique property reference number (UPRN) and geo-spatial co-ordinates to each home address. These can then be used to map the address to particular geographies. Where it was not possible to assign a unique property reference number to an address using the Pointer database, or where the secondary dataset contained only postcode information, the Central Postcode Directory was used to map home address postcodes to higher geographies. A small proportion of records with unknown geography were apportioned based on the spatial characteristics of known records. Further Information NISRA Mid-year Population Estimates webpage Contact: NISRA Customer Services 02890 255156 census@nisra.gov.uk Responsible Statistician: Jonathan Harvey

Description of Data Notes: The estimates are produced using a variety of data sources and statistical models. Therefore small estimates should not be taken to refer to particular individuals. The migration element of the components of change have been largely derived from a data source which is known to be deficient in recording young adult males and outflows from Northern Ireland. Therefore the estimates are subject to adjustment to account for this and, while deemed acceptable for their use, will not provide definitive numbers of the population in the reported groups/areas. Further information is available in the Limitations section of the statistical bulletin: NISRA 2023 Mid-year Population Estimates webpage Time Period Estimates are provided for mid-2001 to mid-2023. Methodology The cohort-component method was used to create the population estimates for 2023. This method updates the Census estimates by 'ageing on' populations and applying information on births, deaths and migration. Further information is available at: NISRA 2023 Mid-year Population Estimates webpage Geographic Referencing Population Estimates are based on a large number of secondary datasets. Where the full address was available, the Pointer Address database was used to allocate a unique property reference number (UPRN) and geo-spatial co-ordinates to each home address. These can then be used to map the address to particular geographies. Where it was not possible to assign a unique property reference number to an address using the Pointer database, or where the secondary dataset contained only postcode information, the Central Postcode Directory was used to map home address postcodes to higher geographies. A small proportion of records with unknown geography were apportioned based on the spatial characteristics of known records. Further Information NISRA Mid-year Population Estimates webpage Contact: NISRA Customer Services 02890 255156 census@nisra.gov.uk Responsible Statistician: Shauna Dunlop

Counts of the Northern Ireland population at low level geography as at 30th June by sex and selected age groups Source agency: Northern Ireland Statistics and Research Agency Designation: Official Statistics not designated as National Statistics Language: English Alternative title: SAPEs

Population estimates relate to the population as of 30th June each year, and therefore are often referred to as mid-year estimates. They are used to allocate public funds to the Northern Ireland Executive through the Barnett formula and are widely used by Northern Ireland government departments for the planning of services, such as health and education.

These statistics are also of interest to those involved in research and academia. They are widely used to express other statistics as a rate, and thus enable comparisons across the United Kingdom and other countries.

Furthermore, population estimates form the basis for future population statistics such as population projections.

This dataset provides Census 2021 estimates that classify usual residents in Northern Ireland by single year of age, and by sex. The estimates are as at census day, 21 March 2021.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

This dataset provides Census 2021 estimates that classify households in Northern Ireland, with at least one usual resident, by household size. It also includes an estimate of the number of usual residents living in households and average household size. The estimates are as at census day, 21 March 2021.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

Average household size is a calculation of the usually resident population living in households divided by the number of households.

The quality assurance report can be found here

Description of Data Population estimates for the 850 Super Data Zones in Northern Ireland were published on 29th May 2025. Time Period Estimates are provided for mid-2021 to mid-2023. Notes: 1. Estimated populations are given as of 30th June for the year noted, rounded to the nearest person. 2. Rounding for estimates at this geographic level is independent. As such, figures may not add to higher geography totals. Methodology The population estimates for small geographical areas are created from an average of two statistical methods: the ratio change and cohort-component methods. The ratio change method applies the change in secondary (typically administrative) data sources to Census estimates. The 2023 small geographical area estimates use a single statistical dataset which has been created by amalgamating a series of different administrative data sources. This statistical dataset is a de-duplicated admin based estimate for the usually resident population of NI. The cohort-component method updates the Census estimates by ‘ageing on’ populations and applying information on births, deaths and migration. An average of both methods is taken and constrained to the published population figures. Further information is available at: NISRA 2023 Mid-year Population Estimates webpage Geographic Referencing Population Estimates are based on a large number of secondary datasets. Where the full address was available, the Pointer Address database was used to allocate a unique property reference number (UPRN) and geo-spatial co-ordinates to each home address. These can then be used to map the address to particular geographies. Where it was not possible to assign a unique property reference number to an address using the Pointer database, or where the secondary dataset contained only postcode information, the Central Postcode Directory was used to map home address postcodes to higher geographies. A small proportion of records with unknown geography were apportioned based on the spatial characteristics of known records. Further Information The next estimates of the population for Northern Ireland will be released later in 2025. Contact: NISRA Customer Services 02890 255156 census@nisra.gov.uk Responsible Statistician: Shauna Dunlop

National population projections by age and gender are produced every two years for the UK and each of the UK constituent countries by the Office for National Statistics (ONS) on behalf of the National Statistician and the Registrars General of Scotland and Northern Ireland. Principal Projections are produced based on long-term assumptions about future fertility, mortality and migration levels, with variant projections being produced from various alternative assumptions – usually in the form of high/low variants and their combinations. National population projections provide an estimate of the future size and age structure of the population of Northern Ireland. Population projections are widely used in policy development in areas such as housing, healthcare and education.

Following the publication of Northern Ireland level population projections, NISRA subsequently produces official sub-national population projections for areas within Northern Ireland. These sub-national projections are based on 2018 mid-year estimates and assumptions regarding future fertility, mortality and migration for areas within Northern Ireland. In keeping with past practice, these local level projections are constrained to the most recent Northern Ireland level population projections. Projections are available for both current and former Local Government Districts, Health and Social Care Trusts and former Education and Library Boards.

Period life expectancy by age and sex for Northern Ireland. Each national life table is based on population estimates, births and deaths for a period of three consecutive years. Tables are published annually.

National population projections by age and gender are produced every two years for the UK and each of the UK constituent countries by the Office for National Statistics (ONS) on behalf of the National Statistician and the Registrars General of Scotland and Northern Ireland. Principal Projections are produced based on long-term assumptions about future fertility, mortality and migration levels, with variant projections being produced from various alternative assumptions – usually in the form of high/low variants and their combinations. National population projections provide an estimate of the future size and age structure of the population of Northern Ireland. Population projections are widely used in policy development in areas such as housing, healthcare and education.

Description of Data Notes: The estimates are produced using a variety of data sources and statistical models. Therefore small estimates should not be taken to refer to particular individuals. The migration element of the components of change have been largely derived from a data source which is known to be deficient in recording young adult males and outflows from Northern Ireland. Therefore the estimates are subject to adjustment to account for this and, while deemed acceptable for their use, will not provide definitive numbers of the population in the reported groups/areas. Further information is available in the Limitations section of the statistical bulletin: NISRA 2024 Mid-year Population Estimates webpage Time Period Estimates are provided for mid-1971 to mid-2024. Methodology The cohort-component method was used to create the population estimates for 2024. This method updates the Census estimates by 'ageing on' populations and applying information on births, deaths and migration. Further information is available at: NISRA 2024 Mid-year Population Estimates webpage Geographic Referencing Population Estimates are based on a large number of secondary datasets. Where the full address was available, the Pointer Address database was used to allocate a unique property reference number (UPRN) and geo-spatial co-ordinates to each home address. These can then be used to map the address to particular geographies. Where it was not possible to assign a unique property reference number to an address using the Pointer database, or where the secondary dataset contained only postcode information, the Central Postcode Directory was used to map home address postcodes to higher geographies. A small proportion of records with unknown geography were apportioned based on the spatial characteristics of known records. Further Information NISRA Mid-year Population Estimates webpage Contact: NISRA Customer Services 02890 255156 census@nisra.gov.uk Responsible Statistician: Shauna Dunlop

This dataset provides Census 2021 estimates for the number of usual residents in Northern Ireland. The estimates are as at census day, 21 March 2021.

The census collected information on the usually resident population of Northern Ireland on census day (21 March 2021). Initial contact letters or questionnaire packs were delivered to every household and communal establishment, and residents were asked to complete online or return the questionnaire with information as correct on census day. Special arrangements were made to enumerate special groups such as students, members of the Travellers Community, HM Forces personnel etc. The Census Coverage Survey (an independent doorstep survey) followed between 12 May and 29 June 2021 and was used to adjust the census counts for under-enumeration.

To find out how Data Zones and Super Data Zones have been developed, and how other Northern Ireland geographies can be approximated, please read the notes here

The quality assurance report can be found here