Population statistics and sources guide

Type of estimate

New experimental statistics about the population or supporting data and research

Release information

• Data sources: Real-Time Information and nationality from Migrant Worker Scan.

• Latest reference period: June 2021.

• Geographical coverage: UK.

• Lowest geographical breakdown: regions -- Nomenclature Units for Territorial Statistics Level 1.

• Population definition: employees.

• Publication type: research.

Uses and guidance

Provides information on the number of employees to guide decisions on the need for, and methods used in, future reweighting exercises of the Labour Force Survey (LFS). The different definition to other population estimates means it is not comparable with official estimates of the population.

The estimates published on 15 March 2022 provide an update to the ad hoc estimates published in March 2021. These are not indicative migration or population estimates and should not be used as such. Reweighted LFS estimates were published on 14 June 2022 for periods from January to March 2020, incorporating the latest RTI by nationality (from MWS) data. More information on this is available in the Impact of reweighting on Labour Force Survey key indicators article.

Publication

Employments from Pay As You Earn Real Time Information: Ad hoc estimates of payrolled employees by NUTS1 region and nationality, seasonally adjusted. Published 15 March 2022.

Type of estimate

New experimental statistics about the population or supporting data and research.

Release information

• Data sources: Labour Force Survey (LFS).

• Latest reference period: currently completed annually.

• Geographical coverage: UK.

• Lowest geographical breakdown: regions - International Territorial Level 1.

• Population definition: usual residents of households.

• Publication type: research.

Uses and guidance

The main use of populations within the LFS and Annual Population Survey (APS) data is to provide contextual comparisons of the labour markets for different areas, and for use as a denominator for calculating rates from within the published LFS and APS datasets. They are not comparable with the official mid-year population estimates.

Publication date

14 June 2022

Reweighted Labour Force Survey data were published in our Labour Market bulletin on 14 June 2022. More information on this is available in the Impact of reweighting on Labour Force Survey key indicators article.

We are looking at the impact of this alongside the release of Census 2021 estimates, and what effect this has on the best estimates of the population by country of birth and nationality. As a result, future publications of the Population of the UK by country of birth and nationality: year ending June 2021 are being reviewed and a decision on the next publication will be made by November 2022.

Type of estimate

Official statistics from Census 2021, giving a picture of the population in March 2021.

Release information

• Data sources: Census 2021.

• Latest reference period: 21 March 2021.

• Geographical coverage: England, and Wales Lowest geographical breakdown: local authority district.

• Population definition: all resident people on Census night - households and communal establishments.

• Publication type: official estimate of population as of 21 March 2021.

Uses and guidance

Census 2021 is our best estimate of the population of England and Wales as on Census Day. Subject to our final quality assurance processes and engagement with local authority users of census statistics, it will underpin the official mid-year population estimates, which will be published later in the year.

Publication date

On 28 June 2022 we released the First results from Census 2021 in England and Wales.

We published five datasets containing population and household estimates for England and for Wales, rounded to the nearest 100 at local authority level. These were

• usual resident population by sex

• usual resident population by 5-year age group

• usual resident population by sex and 5-year age group

• usual resident population density

• number of households

To explain these data, we published two statistical bulletins, one focused on England and Wales and one focused on Wales. In these, we discuss the population size and change from 2011, population density and number of households. 

Additionally, to support the data we have published a Quality and Methods Information (QMI) report, about the quality of the data to:

• maximise the quality of Census 2021 population estimates report

• give an overview of the estimation and quality assurance processes we used to create and ensure the estimates are fit for purpose

• share a local authority comparison tool, letting you compare estimates for local authorities with other sources of data

You may also want to explore the Interactive content from the Census 2021 first results, including:

• How the population changed where you live: Census 2021 article that "scrolly-tells" you about how the population has changed in different local authority areas and how they compare with others across England and Wales

• the Census 2021 population map game, testing your knowledge of the population of local authorities

Type of estimate

New research outputs about the population, supporting data and research.

Release information

• Data sources: predominantly admin data.

• Latest reference period: 2022.

• Geographical coverage: England and Wales.

• Lowest geographical breakdown: synthetic example at local authority district level.

• Population definition: target is usual residents of households and communal establishments.

• Publication type: research.

Uses and guidance

This research report updates on progress towards a proof of concept for age and sex profiles of the population for local authorities on a 2022 base using the Dynamic Population Model (DPM).

Providing these timely population totals will allow decision-makers to see quickly when things have changed, to ensure that public services are targeted to the right population groups in the right places. This has been very important to understand as we emerge from the coronavirus pandemic, and since our departure from the EU.

The example population estimates presented in this report are based on synthetic data for a single local authority with a population typical of areas that contain a university. These outputs are for illustrative purposes only and should not be used in decision-making.

Publication date

On 14 July we outlined the new methods we are developing to produce estimates of the size of the population and population change using a dynamic population model (DPM). This article explains what the DPM is, how it differs from the existing method for creating population estimates, the data it uses and the outputs it will produce.

Alongside this, we have also published an International migration statistical design progress report: July 2022 article explaining how we intend to move through the next stages of the international migration transformation programme. Users require international migration estimates which are timely, frequent and granular. These estimates are also a main input to the DPM as we plan to meet both requirements. This article explains our plans to meet both requirements. We aim to publish the latest set of international migration flow estimates for the year ending 2022, derived from administrative data, in November 2022.

These articles are the first in a series of publications over the coming months which will outline our plans to use a DPM to produce coherent population and migration estimates.

Type of estimate

New experimental statistics about the population or supporting data and research.

Research information

• Data sources: Annual Population Survey (APS).

• Latest reference period: currently done annually.

• Geographical coverage: UK.

• Lowest geographical breakdown: local authority district.

• Population definition: usual residents of households.

• Publication type: research.

Uses and guidance

The main use of populations within the Labour Force Survey (LFS) and APS data is to provide contextual comparisons of the labour markets for different areas. It is also used as a denominator for calculating rates from within the published LFS and APS datasets. They are not comparable with the official mid-year population estimates and so, although they feed into the production of other official statistics, they are not an official measure of the population themselves.

Publication date

16 August 2022

Reweighted APS data will be published in our Labour Market bulletin on 16 August 2022. More information on this is available in the Impact of reweighting on Labour Force Survey key indicators article.

Type of estimate

New research outputs about the population, supporting data and research.

Release information

• Data sources: predominantly admin data.
• Latest reference period: to June 2022.
• Geographical coverage: England and Wales .
• Lowest geographical breakdown: sample of local authority districts. (November 2022), local authority district (February 2023).
• Population definition: target is usual residents of households and communal establishments.
• Publication type: research.

Uses and guidance

Our latest research on transforming the population statistics system and our ambition to produce monthly population estimates using additional sources of admin data and innovative methods. We included estimates by single year of age and sex from the Dynamic Population Model (DPM) for a sample of 14 Local Authorities in November 2022, and intend to include all local authorities in February 2023.

These will offer a timelier indication of population changes than is available in the official population estimates. There is demand for this from numerous areas of rapid planning and policymaking.

Publication date

23 November 2022: Dynamic population model for local authority case studies in England and Wales: 2011 to 2022; and February 2023

Type of estimate

Official statistics from Census 2021, giving a picture of the population at March 2021.

Release information

• Data sources: Census 2021.

• Latest reference period: 21 March 2021.

• Geographical coverage: England, and Wales.

• Lowest geographical breakdown: output area.

• Population definition: all resident people on Census night - households and communal establishments.

• Publication type: official estimate of population as at 21 March 2021.

Uses and guidance

This release is part of our topic summaries from Census 2021 results and includes univariate data (one variable only) down to output area level where possible. It also includes supporting commentary about demography and migration from Census 2021 in England and Wales.

Census 2021 is our best estimate of the population of England and Wales as of Census Day. It will underpin the official mid-year population estimates, subject to our final quality assurance processes and engagement with local authority users of census statistics.

Publication date

2 November 2022: Demography and migration: Census 2021 in England and Wales

Type of estimate

Official statistics from population and migration statistics from 2021.

Release information

• Data sources: Census 2021, births, deaths and international migration estimates.

• Latest reference period: mid-2021 (year ending 30 June 2021).

• Geographical coverage: UK.

• Lowest geographical breakdown: local authority district.

• Population definition: usual residents of households and communal establishments.

• Publication type: official estimate of the population as at 30 June 2021.

Uses and guidance

This will provide the official annual estimates of the population. They will represent the highest quality annual estimates consistent with previous mid-year estimates produced from the traditional cohort component method of population estimates. These are underpinned by Census 2021 for England, Wales and Northern Ireland, and rolled forward from the 2011 Census for Scotland.

These estimates are useful for planning and policy purposes as well as for use in onward analysis, such as for sampling and weighting surveys and using in projections.

This publication will also include data for mid-2021 population estimates rolled forward from 2011 Census to show areas of inter-censual drift. These estimates are not the official annual estimates of the population that form the main part of this publication but are published for comparison purposes. They are superseded by, and inferior, to the Census 2021-based mid-year estimate described earlier.

Publication date

21 December 2022

Type of estimate

Official statistics about population and migration statistics.

Release information

• Data sources: Annual Population Survey (APS).

• Latest reference period: year ending June 2022.

• Geographical coverage: UK.

• Lowest geographical breakdown: local authority district.

• Population definition: usual residents of households.

• Publication type: official estimate of the population when broken down by country of birth and nationality.

Uses and guidance

The APS is not designed to measure long-term international migration flows but does give insights into changes and size of the non-UK born and non-UK national population. The population estimates in the statistical bulletin that accompanies the publication are referred to as ‘stocks’, but it is not possible to directly compare stocks from the APS with estimates of migration flows. These estimates are also not comparable with the population totals in the official mid-year population estimates.

Publication date

Discontinued. Please see the statement on the Population of the UK by Country of Birth and Nationality series published on 27 October 2022.

We are transforming the way we produce population and migration statistics to make best use of all available data. The Labour Force Survey (LFS)(on which the APS is based) is being transformed to make further improvements to labour market statistics to improve quality, granularity and timeliness.

As part of this transformation journey, we are reviewing the best methods to produce estimates of the UK population. Therefore, the population of the UK by country of birth and nationality series using the APS has been discontinued.

We will produce provisional measures of the non-UK population, depending on user needs and working closely with colleagues in NRS, NISRA and other government departments, including HMRC and the Home Office.

In the interim we have provided an indication of the size of the non-UK born population in our latest migration statistics.

Type of estimate

New experimental statistics about the population or supporting data and research.

Release information

• Data sources: Mid-year population estimates, Census 2021, Higher Education Statistics Authority data, Personal Demographic Service data.

• Latest reference period: 2021.

• Geographical coverage: England and Wales.

• Lowest geographical breakdown: local authority district.

• Population definition: Students and selected age groups of usual residents of households and communal establishments.

• Publication type: research.

Uses and guidance

We are working on case studies of data relating to students in local population estimates, building on our work towards understanding students across administrative data in England and Wales, which we published in November 2021. This analysis used a combination of admin data on health and higher education to understand, among other things, how well the data shows the movements of students into and out of student accommodation.

Our case studies will provide analysis of these features in more detail at the local level, and the first analysis is expected for publication as soon as possible after Census 2021 results are available. This publication was postponed from the originally planned date of March 2022 to enable the completion of Census quality assurance by participating local authorities, and to enable the inclusion of Census 2021 results on students into the analysis.

Publication date

20 January 2023

Type of estimate

Official statistics from 2021-based population and migration statistics.

Release information

• Data sources: 2011 Census, Census 2021, births, deaths and international migration estimates.

• Latest reference period: mid-2020.

• Geographical coverage: England, Wales and Northern Ireland.

• Lowest geographical breakdown: country.

• Population definition: usual residents of households and communal establishments.

• Publication type: official.

Uses and guidance

These are the best population estimates to use for a comparable data time series of estimates with years before the mid-2021 estimates.

Publication date

Early 2023

Type of estimate

New research outputs about the population, supporting data and research.

Release information

• Data sources: predominantly admin data.
• Latest reference period: mid-2021.
• Geographical coverage: England and Wales.
• Lowest geographical breakdown: local authority district level.
• Population definition: target is usual residents of households and communal establishments.
• Publication type: research.

Uses and guidance

The Dynamic Population Model (DPM) uses a range of data sources to produce estimates of the size of the population and population change. Admin-based population estimates (ABPEs) are an important data input into the DPM, which we will now refer to as Statistical Population Datasets (SPDs). This reflects that they are no longer seen as a finished estimate but will be an input to the DPM along with several other sources relating to population and migration. The DPM then combines the sources to provide a coherent set of population and migration outputs.

This research report will explore how SPD v4 compares with Census 2021 population estimates. These estimates are not official estimates of the population but are published to give transparency around the inputs into the DPM and for comparison purposes. They should not be used in decision-making.

Publication date

28 February 2023

Type of estimate

Official statistics from 2021 population and migration statistics from 2021.

Release information

• Data sources: 2011 Census, Census 2021, births, deaths and international migration estimates.

• Latest reference period: mid-2020.

• Geographical coverage: England, Wales, and Northern Ireland.

• Lowest geographical breakdown: local authority district.

• Population definition: usual residents of households and communal establishments.

• Publication type: official.

Uses and guidance

These are the best population estimates to use for a comparable data time series of estimates with years before the mid-2021 estimates.

Publication date

Spring 2023