By answering a sequence of basic questions about our lives and personal circumstances, citizens contribute invaluable population data that builds up a portrait of the nation, in response to which policy decisions on everything from healthcare to public services are drawn up.
In 2021, its findings are likely to prove invaluable in shaping our post-Brexit economy and ongoing recovery from the coronavirus pandemic.
England, Wales and Northern Ireland are all carrying out their surveys this year on schedule but the National Records of Scotland, which organises the Scottish census, has been forced to delay its census by a year until 2022 because of a bureaucratic logjam caused by the Covid-19 outbreak.
Here’s everything you need to know.
What does answering the census involve?
This year marks the first time the survey has been done entirely online, with households sent a 16-digit activation code through the post that is used to login on the ONS website (although you can request a paper version of the form if you prefer).
