• relate to the usually resident population on 30 June of each year

  • a number of data sources are used to compile the population estimates, including the General Register Office (GRO), the International Passenger Survey (IPS), the Higher Education Statistics Agency (HESA), the National Health Service Central Register (NHSCR) and the Ministry of Justice

  • estimates for Scotland and Northern Ireland are produced by the National Records Scotland (NRS) and the Northern Ireland Statistics and Research Agency (NISRA) respectively

  • annually published estimates available from 1981 onwards

The mid-year population estimates are the official set of population estimates for the UK and its constituent countries, the regions of England and Wales and local authorities.

The estimates account for long-term international migrants (people who change their country of usual residence for a period of 12 months or more), but do not account for short-term migrants (people who come to or leave the country for a period of less than 12 months). A combination of registration, survey and administrative data are used to estimate the different components of population change.

The mid-year population estimates are an essential building block for a wide range of National Statistics. They are used directly as a base for other secondary population statistics, such as population projections, population estimates for the very old and population estimates for small geographical areas. They are also used for weighting survey estimates, such as the Labour Force Survey (LFS) and other social surveys to ensure that they are representative of the total population.

External users of the estimates include central and local government and the health sector, where they are used for planning and monitoring service delivery, resource allocation and managing the economy. Other users include commercial companies (for market research), special interest groups and academia.

We quality assure the administrative data used for these statistics to ensure that they are suitable for this purpose. To gain further insight on data quality issues and the impact on statistics, please see Quality Assurance of Administrative Data:

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