Population estimates by output areas, electoral, health and other geographies, England and Wales: mid-2023 and mid-2024, revised mid-2022

• Population estimates for output areas, lower layer Super Output Areas (LSOAs), middle layer Super Output Areas (MSOAs), electoral, health and other geographies for mid-2022 have been revised.
• These revisions make the mid-2022 estimates coherent with the revised local authority population estimates for mid-2022, published in July 2025, and utilise updated Personal Demographics Service data and improvements to data on the population in prisons across England and Wales.
• In the majority of areas, the revisions to population estimates are small; 98.3% of lower layer super output area population estimates for mid-2022 have been revised up or down by less than 2%.
• This publication provides population estimates for statistical, health, and electoral geographies that are consistent with our Population estimates for England and Wales bulletin, published in July 2025.

The data published in this release provide population estimates for Census 2021 lower layer Super Output Areas (LSOAs) and middle layer Super Output Areas (MSOAs) for mid-2023 and mid-2024. They are consistent with the local authority estimates published in July 2025. In addition, estimates for mid-2022 have been revised to be consistent with revised local authority level estimates for mid-2022, which were also published in July 2025.

Estimates for LSOAs by broad age groups, and for MSOAs by five-year age groups are accredited official statistics. Estimates at greater levels of disaggregation, for example by single year of age and for output areas, are provided as supporting information. This enables aggregation to meet individual user requirements. Estimates for output areas are only available from NOMIS.

This release includes estimates for Parliamentary constituencies, electoral wards, integrated care boards, and National Parks, alongside population estimates for statistical geographies. Estimates by Parliamentary constituencies and electoral wards are published exclusively on NOMIS.

Estimates for electoral wards, Parliamentary constituencies, and National Parks are official statistics in development. Estimates for integrated care boards are aggregated directly from lower layer Super Output Areas (LSOAs) and are accredited official statistics.

In July 2025, local authority estimates were revised to incorporate improved international and internal migration data, further information can be found in our Population estimates for England and Wales: mid-2024 bulletin.

Population estimates for output areas, lower layer Super Output Areas (LSOAs), middle layer Super Output Areas (MSOAs), electoral, health and other geographies for mid-2022 have been revised. These revisions make the mid-2022 estimates coherent with the revised local authority population estimates for mid-2022 published in July 2025 and utilise updated Personal Demographics Service data and improvements to data on the population in prisons across England and Wales.

In the majority of areas, the revisions to population estimates are small, reflecting that changes to mid-2022 local authority estimates were relatively small (99% of local authority level population estimates were revised up or down by less than 0.5%).

Figure 1 shows the impact of revisions at LSOA, output area (OA) and ward level.

• At LSOA level, 98.3% of areas are revised up or down by 2% or less.

• At output area level, 60.1% of areas are revised up or down by 2% or less, 94.2% of output areas are revised up or down by 5% or less.

• For wards (2025 boundaries), 99.6% are revised up or down by 2% or less.

Population estimates

Population estimates provide statistics on the size and age structure of the population. They are the official source of estimated population size in between censuses and inform a wide range of official statistics.

Mid-year

Mid-year refers to 30 June of any given year.

Usually resident population

These data estimate the "usually resident population". This is the standard United Nations (UN) definition and includes only people who reside in a country for 12 months or more, making them usually resident in that country. As such, visitors and short-term migrants are excluded.

Super output areas

Super Output Areas (SOAs) are statistical geographies designed to improve the reporting of small area statistics. They are built from groups of census Output Areas, are of a consistent population size, and are not subject to boundary changes between censuses. A simple guide to the UK geographical areas frequently used for the publication of official statistics can be found on our A beginner's guide to the UK geography web page.

There are two broad types of small area population estimates, both of which are included in this release.

The main products are the estimates for Super Output Areas (SOAs), which are based on Census 2021 and rolled forward annually using a ratio change methodology. This approach uses the change in the population recorded in the Personal Demographics Service (based on GP registrations) as an indicator of the change in the true population.

Estimates for lower layer SOAs (LSOAs) by broad ages and middle layer SOAs (MSOAs) by five-year age groups are accredited official statistics. Estimates at greater levels of disaggregation, for example by single year of age, are provided as supporting information only. More information can be found in our Small Area Population Estimates: Summary of methodology review and research update.

The remainder of our small area population estimates products relate to a range of different geographic areas and are derived directly from the SOA figures. First, estimates for LSOAs are broken down to output area (OA) level using an apportionment approach. These OA estimates are then aggregated to produce estimates for electoral wards and Westminster Parliamentary constituencies on a best-fit basis. Estimates for National Parks are also calculated from the OA-level data.

Electoral wards, Westminster Parliamentary constituencies, and National Parks are official statistics in development. Estimates for health geographies are aggregated directly from LSOAs and are accredited official statistics.

The estimates for output areas, along with geography lookups from the Office for National Statistics (ONS) Open Geography Portal, enable additional geographic breakdowns to be produced.

Small area population estimates are used by both central government departments and local authorities for a range of purposes. These include planning and monitoring of services and as denominators for the calculation of various rates and indicators.

The mid-2022 to mid-2024 small area population estimates covered by this release are fully consistent with our mid-year population estimates, including local authorities, regions, and the national total for England and Wales. A full description of the methods used to calculate all small area population estimates is available in our methodology note.

In some local authorities, the number of people included on the Personal Demographics Service in any current year may have increased or decreased in many LSOAs and MSOAs, compared with the previous year. This may be because of changes in administrative practices or may reflect genuine population change. The process of constraining LSOA and MSOA estimates to previously published local authority population estimates means that this pattern is not automatically reflected in the mid-year estimates.

All population estimates are subject to statistical uncertainty, and this is generally highest for estimates of small areas, areas with high levels of population churn, and at the end of the inter-census period.

In Spring 2026, we plan to publish an update on our research into new methods for population estimates at the LSOA level. This will enable users of small area population estimates to provide feedback and help determine the future approach to population estimates for all the geographies contained in this release. While we develop the methods for the future, we plan to use methods used for this release in 2026. 

More quality and methodology information

More quality and methodology information (QMI) on strengths, limitations, appropriate uses, and how the data were created is available in our Population estimates by output areas, electoral, health and other geographies QMI.