Overview of Census 2021 design plans

It is now just under six months until the Census in England and Wales takes place on 21 March 2021. This major event requires considerable planning, design and quality assurance. Our plans for 2021 build upon lessons learned from previous censuses, the 2019 Rehearsal, best practice in statistical design and our research and testing.

The census is the largest statistical exercise that the Office for National Statistics (ONS) undertakes, producing statistics that inform all areas of public life and underpin social and economic policy. It is essential that we get it right for the good of the nation, and that the whole population has the chance to provide the information that can help to ensure their communities are well served.

On 1 October 2020, we set out in three articles our plans for:

• running the 2021 operation safely and securely during the coronavirus pandemic
• how we are further improving the plans for the operations following the 2019 Collection Rehearsal
• our overall statistical design for Census 2021, including the approach to quality assurance

In the light of the coronavirus (COVID-19) pandemic, we have refined our plans to ensure that everyone can provide their information safely and securely.

We have already started to print the census questionnaires and our Census Engagement Managers are now in post. As we continue our plans with contingencies in place, we are now in a strong position and are confident of delivering an outstanding Census in 2021.

In 2019, we undertook a Collection Rehearsal, which showed that our systems worked and integrated end-to-end in the way we expected. This enabled us to achieve response rates comparable with our rehearsal in 2009. 

The rehearsal taught us many lessons, including the need to improve our management information to quickly identify areas or groups with lower than expected response rates. It also identified the need to improve our recruitment and training processes. Full details can be found in the full evaluation report for 2019 collection rehearsal in England and Wales.

We have also learnt lessons from our close work with other National Statistics Institutes that undertake a traditional census – most notably New Zealand, Australia, Canada and the USA.

The statistical design for Census 2021 sets out our approach to ensuring that we count everyone and only count them once. It sets out a range of methods that have been used in the past and enhancements to these to make use of the increased availability of Management Information.

At the heart of the design is maximising response and minimising undercounts. The rehearsal identified the importance of having quick and timely management information, a well-trained field force who encourage response and very strong community engagement. We have built on all these areas since the rehearsal.

The coronavirus (COVID-19) has impacted on our planning for Census 2021. Our design now means we can conduct the main census field operation without anyone ever needing to enter a house. All contacts will be socially distanced. Our recruitment and training have been moved wholly online. Find out more about the operational planning response to COVID-19 for Census 2021.

With community engagement being important, we are working with communities to ensure we engage safely in line with the government's coronavirus guidance yet reach out using new forums that have emerged during the pandemic.

We recognise though that even with all these systems tested and in place, we may still need to deploy statistical methodologies, as in the last census, to deal with unavoidable undercounts in specific groups or areas. We will build upon our Census Coverage Survey approach with increased use of administrative data to help identify and deal with these undercounts.

Underpinning all of this is quality assurance for Census 2021. Our whole approach must have the trust of our users.

We will continue to monitor and refine our plans as guidance changes over the coming months to ensure we run a successful, safe and secure Census in 2021 in England and Wales. We are also working with National Records Scotland and the Northern Ireland Statistics and Research Agency to ensure we continue to produce the UK-wide population statistics necessary.

You can find out more about the design of the census and what we have done to develop the questions for 2021, as well as the latest news and updates on progress towards census 2021.

The National Records of Scotland and the Northern Ireland Statistics and Research Agency have published information on their census design and plans, for Scotland and Northern Ireland, respectively.