The once-in-a-decade survey has been carried out every 10 years since 1801, with the exception of 1941. This year it will be the first census to be run predominantly online, with households receiving a letter with a unique access code, allowing them to complete the questionnaire on their computers, phones or tablets. Census day will officially be on Sunday March 21, but there will be an extensive window in which to complete the survey for households both locally and across the country, who will receive letters with online codes allowing them to take part from early March up to the beginning of May. The census will include questions about your sex, age, work, health, education, household size and ethnicity. And, for the first time, there will be a question asking people whether they have served in the armed forces, as well as voluntary questions for those aged 16 and over on sexual orientation and gender identity. Results will be available within 12 months, although personal records will be locked away for 100 years, to be kept safe for future generations. The Office for National Statistics says it aims to make things as easy as possible for everyone and there is a general help area on the census website. It covers everything from who to include on the questionnaire to how to answer each question. For more information, people are urged to visit www.census.gov.uk or call the customer contact centre on 0800 141 2021 from February 22 2021.