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Testing for the 2021 Census

In preparation for the 2021 Census, the Office for National Statistics (ONS) is carrying out a census test of more than 200,000 households in England and Wales on 9 April 2017.

With the next census set to be predominantly online, the 2017 Test is designed to check that systems and services are working correctly, while also trying out new questions that may be used in 2021. Included in this test are proposed new questions on sexual identity1 and volunteering.

ONS will be testing its census on 100,000 households across 7 selected local authorities2. In these areas census officers will be out encouraging and offering help to households yet to respond.

There will also be a test of another 100,000 randomly-selected households across the rest of England and Wales, as well as a test of 8,000 households on the Isle of Wight of how well ONS can support anyone with difficulty going online to fill in their census questionnaire.

“The census is important to all of us, as it’s used to help plan and fund a range of services for communities such as transport, education and health,” Acting Census Director Ben Humberstone said.

“The 2017 Test will give us a great chance to test our plans for the 2021 Census – including questions, systems and services. We can then learn and make improvements before census day.

“If your household receives an invite, I’d like to encourage you to take part in this test. It will take just 10 minutes per person. If you do, you’ll be helping us shape the 2021 Census and therefore the future of both your area and our country.”

Households, if selected to take part in this test, will receive a letter with a unique access code in order to fill in their online questionnaire. All they need to do is head online to and answer a few questions about themselves and the people who will share their household with them on 9 April. Some households may receive a paper questionnaire.

Whatever you tell the census test will be in strictest confidence and will be used by ONS only to assess questions and systems ahead of 2021.

For more information visit or contact the census helpline on 0300 068 3001.

Background notes

  1. ONS is using a split sample to test the question on sexual identity. Therefore not all households will receive a questionnaire with that question in it.

  2. The 7 local authorities involved in the test are Barnsley Metropolitan Borough Council, Blackpool Borough Council, Powys County Council (Cyngor Sir Powys), Sheffield City Council, South Somerset District Council, Southwark Council, West Dorset District Council.

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