UK Census data

Working with the Office for National Statistics and National Records of Scotland to provide census data for the UK.


NISRA is responsible for planning and conducting Census 2021 in Northern Ireland. National Records of Scotland (NRS) is responsible for Census 2022 in Scotland, while the Office for National Statistics (ONS) is responsible for Census 2021 in England and Wales. In addition, ONS coordinates the production of census statistics for the UK.

The previous UK censuses took place on 27 March 2011. Following this, the ONS disseminated Census 2011 statistics for the UK via its UK censuses data webpage. It also produced a 2011 Census UK Comparability Report (PDF 930KB) showing comparability of the census questions and outputs across the UK.

NISRA and ONS conducted their censuses simultaneously in March 2021, while NRS will be undertaking the census in Scotland in March 2022. This will result in a one-year difference in reference dates and will impact the comparability of the UK census data. The three census offices are working closely to develop UK-wide census results that best support the information needs of users where possible. This involves consideration of how best to meet the challenges around comparability, coherence, timeliness and accessibility of the information.

UK Harmonisation

In order to support harmonisation activities and coordinate engagement with users of UK data, we meet regularly with ONS, Welsh Government and NRS. We are working closely to ensure we continue to produce the UK-wide population statistics necessary and will continue to engage with users through the ONS-led UK Data User Working Group. UK population estimates for mid-2021 will still be delivered, but they will be based on the 2021 Censuses in Northern Ireland and England and Wales and “rolled-forward” from the 2011 Census in Scotland.

There have been a number of updates to the original statement of agreement (PDF 225KB) between the National Statistician and the Registrars General for Northern Ireland and Scotland on the conduct of the 2021 Censuses in the UK outlining the progress made by three census offices towards harmonisation:

The censuses across the UK have been designed to be conducted in a consistent manner. The three census offices collaborate effectively through multiple topic-based working groups to harmonise elements of Census 2021 where possible and facilitate the production of UK-level census data products.

Owing to varying user requirements, there will be differences in some of the questions asked in the upcoming census across the UK. Furthermore, there will be some differences in the data processing methods employed. As we move forward, the three offices will provide information on ongoing harmonisation activities on their respective websites. Work will continue at pace to share the lessons learned, best practice from each census office and to identify and explain to stakeholders any areas where UK harmonisation is not achievable.

Are you a UK data user?

A new user working group has been set up for UK census data for 2021 and 2022. The group will be an opportunity for the three UK census offices and UK census data users to share information and feedback.

Membership currently includes the UK census offices, academics, researchers, representatives from local authorities and councils, central government, charities, and commercial organisations. This group is looking for UK census data users in Northern Ireland to understand what UK data they are using and what would be useful.

In March and April 2021, a survey was sent to members of the User Working Group for UK Census 2021 and 2022 Data. The results are helping to steer the direction and priorities of the group. The survey included questions on:

  • what UK census data is used and what for
  • geographical and topic needs
  • priorities
  • any other issues about UK census data

The survey responses are being used to help prioritise the work of the group.

If you are interested in joining this working group, please contact and help shape the provision of UK census data for 2021 and 2022.

More information about UK census data