The Census of India is a decennial (once every ten years) statistical exercise and a legal provision for the systematic collection, compilation, analysis, and dissemination of demographic, social, and economic data pertaining to all persons in the country. The population census is a Union Subject listed at serial number 69 of the Seventh Schedule under Article 246 of the Constitution of India. The first non-synchronous census in India was conducted in 1872 under Viceroy Lord Mayo, but the first synchronous census was taken in 1881. Since then, the census has been conducted uninterruptedly every ten years, with the last one held in 2011.
Post-independence, the census is conducted under the provisions of the Census Act, 1948, which was piloted by Sardar Vallabhbhai Patel. This Act empowers the Central Government to take the census and appoint the necessary staff. The responsibility for conducting the census rests with the Office of the Registrar General and Census Commissioner of India under the Ministry of Home Affairs. A key provision of the Census Act, 1948, is that the information collected from an individual is confidential, not open to inspection, and not admissible as evidence in any court, except for a prosecution under the Act itself (Section 15). The data collected is crucial for administration, planning, policy-making, and the demarcation of constituencies for Parliament and State legislative assemblies.
The census was postponed from 2021 due to the COVID-19 pandemic, making the upcoming Census 2027 the 16th in the series and the 8th since independence. The Census 2027 marks a significant change as it will be the first fully digital census using a mobile application and allowing for online self-enumeration. Furthermore, it will include a comprehensive caste enumeration for all communities, which is the first such exercise since 1931. The census is conducted in two phases: the House Listing and Housing Census, followed by the Population Enumeration.