Census 2021 outputs: content design and release phase proposals

Closes 5 Oct 2021

3d: Age, country of birth and other classifications



We’ve updated other classifications used in 2011, to reflect changes in the questions and response options for Census 2021. In general, users will be able to find equivalents to 2011 data.

All classifications are contained in Draft proposals for outputs data content (XLS, 610KB). The age bands contained within each age classification are in the ‘Resident_age’ tab, and the groups contained within each country classification are contained are in the ‘COB’ tab.

We will finalise these classifications with the information you provide. Please provide as much detail as possible to justify your data needs. An example of this might include what policy or planning decisions would the data analysis affect?


In 2011, we used around 55 different age classifications in the standard outputs. The different age classifications aimed to meet users’ needs related to different topics. For example, these included employment or education. To reflect our updated approach for dissemination, particularly the new capability for users to build their own tables, we’ve reviewed the classifications needed for each topic.

This work has resulted in a proposal to reduce the number of classifications by almost half. We’ve done this by creating simple groupings of classifications that get progressively more detailed for each topic. We hope this will make navigating the different classifications easier for users.

Please rank the following factors in order of importance in relation to your needs for undertaking analysis by age.

'1’ is most important, and ‘5’ is least important. If a factor is not important at all, please respond ‘Not important’

Do our proposals for a reduced set of age classifications meet your needs?
Country of birth

In 2011, we divided the Country of Birth output groupings for EU member countries into two groups according to when those countries joined. These groups were:

  • countries that joined the EU before 2001.
  • countries that joined the EU between 2002 and 2011.

Since 2011, Croatia has joined the EU and the UK has left the EU. None of the other classifications based on countries, such as national identity or country of second address, contain this grouping. Instead, the three main categories that we propose are:

  • Europe: United Kingdom
  • Europe: Ireland
  • Europe: Other Europe

These will be split into more groups in the detailed classifications.

Do our proposals for simplified country of birth classification, removing detail of when a country joined the EU, meet your needs?
Other classifications with more detail added

Other impacted questions include type of accommodation, central heating, marital status, second address, disability, and unpaid care. The classifications with the most potential to change, in both content and presentation, are the ethnic group classifications. 

Classifications that have significantly changed since 2011 Census

Topic Description of change
Type of accommodation We’ve added a new category of “a flat, maisonette or apartment: part of another converted building (for example, former school, church or warehouse)”.
Central heating

We’ve split the category “Gas” into “Mains gas” and “Tank or bottled gas”.

We’ve split the category “Solid fuel” into “Wood (for example, logs, waste wood or pellets)” and “Solid fuel (for example, coal)”.

We’ve split the category “Other central heating” into “Renewable energy (for example, solar thermal or heat pumps)”, “District or communal heat network” and “Other”.
Marital status A second question followed the marital status question. That second question asked who the marriage or civil partnership was with. This included the options “Someone of the opposite sex” and “Someone of the same sex”.
Second Address

We’ve split the category “Other” into “Partner’s address” and “Other”.


We’ve reworded the questions on physical or mental health conditions or illness, to align with the GSS Harmonised standard questions. This means the census now collects data more closely aligned with the definition of disability in the Equality Act 2010.

As part of this process, we split the question into two parts. The first part asked if the respondent had a condition or illness, and the second part asked if it limited their day-to-day activities.

In the 2011 Census, the category “No” encompassed two groups of people. This included those without a condition or illness and those with a condition or illness that did not impact their day-to-day life. Splitting the question into two parts means these two groups can now be identified separately.
Unpaid care The range of response options was increased.The option 'Yes, 1 - 19 hours a week' was split into two categories, which are 'Yes, 9 hours a week or less' and 'Yes, 10 to 19 hours a week'.The option 'Yes, 20 to 49 hours a week' was split into two categories 'Yes, 20 to 34 hours a week' and 'Yes, 35 to 49 hours a week'.
For which topics do you intend to use the additional detail provided in Census 2021?

Select all that apply. 

What would be the impact of including additional detail from any of the variables listed above?