Quarterly update on population and migration statistics: March 2026

We have concluded that established methods for our mid-year population estimates should continue to be used, following a review against the published decision criteria and the announcement of a census in 2031. These methods are outlined in our Population estimates for England and Wales, mid-2024: methods guide. Using the established methods will ensure that population estimates can be produced reliably, with efficient and sustainable systems and processes.

Admin-based population estimates (ABPEs) are not being adopted as official estimates. ABPE refers to a method of producing population estimates applying a statistical model to administrative data. Administrative data collected by other organisations for their own administrative or operational purposes continue to play a critical role, whichever method is used for population estimates.

We are moving to a model of continuous improvement of our population estimates, drawing on the research and experiences of developing ABPEs. We will make iterative improvements to the data and methods that underpin the components of population change, with a focus on internal migration and disaggregation of long-term international migration (LTIM) estimates to local-authority level.

We have listened to user feedback and expert views to make this decision.

We examine one of the criteria (accuracy and reliability) in our Evaluating the accuracy of the ABPEs for England and Wales methodology. We found that differences between the ABPEs and official estimates are small; ABPEs were 0.1% lower at a national level than the latest official population estimates, as described in our Population estimates for England and Wales: mid-2024 bulletin. These comparisons have given additional assurance at a national level that current official estimates are robust and have helped to identify areas for further research. More information can be found in our Evaluating the accuracy of ABPEs methodology and in our Admin-based population estimates: local authority case studies, England and Wales, mid-2024 article.

Current official mid-year estimates already use administrative data. We intend to improve on these iteratively, including expanding the uses and methods of administrative data sources (such as NHS data, tax and benefit data, and Home Office border data), which are included in our existing approaches.

This decision has also been based on user needs and feedback, including assessing the potential impact a "step-change" to ABPEs could have on UK population estimates. Our proposed approach will:

• provide a stable framework for addressing priority user needs for high-quality population statistics in the period between censuses through publishing consistent outputs that are based on robust, reproducible methods

• make the most of research undertaken to date, acknowledging the value of existing work

• support delivery of improvements to our core population and migration statistics, as required under our Economic Statistics Plan

• complement proposals for Census 2031, ensuring alignment within the population statistics system

• deliver on the UK Statistics Authority's recommendation to develop statistical outputs using administrative data that represent society

When we publish mid-2025 estimates this summer, we will revise the mid-2022, mid-2023 and mid-2024 population estimates to incorporate improvements to long-term international migration estimates.

User engagement

Our upcoming Population statistics system webinar on 12 March 2026 will explain how population statistics fit together, including births, deaths and migration, which all feed through to our population projections. Sign up to the webinar on the Eventbrite page.

The approach set out in our Admin-based population estimates; England and Wales engagement plan 2025 to 2026 will inform our continued engagement with users of population estimates.

We will update on our plans for publication through our monthly newsletters and in future editions of this quarterly update article.

Our consultation on the content for Census 2031 in England and Wales closed on 4 February 2026.

We have published further detail on the evaluation criteria for analysing responses in our Evaluation criteria article. We will publish a response update on the consultation around 12 weeks after the consultation closing date. We then plan to publish detailed reports on consultation analysis in late summer 2026.

We have published our Census 2031 Strategy for England and Wales, which covers the mission, vision, goals, and objectives for the next census. We have also set out information on the 2027 Census test, which will be the first large-scale test of data collection in the census programme and will inform design decisions for the census. We expect to publish more information soon on the Census 2031 design.

We will publish our National population projections (NPPs): 2024-based bulletin for the UK in April. We have been working closely with experts and users to develop the mortality, fertility and migration assumptions that will be used for these projections. These assumptions will take the latest trends in long-term international migration into account.

We will hold a webinar to explain the latest NPPs following the release of our 2024-based bulletin.

The next set of subnational population projections (SNPPs) will be 2026-based and are scheduled to be released in 2028. We are redeveloping our system for producing SNPPs. We will be seeking expert input and advice on the methods and data used in our systems and the release redevelopment. If you would like to support this work, please contact us at pop.info@ons.gov.uk.

We intend to publish our 2026-based household projections in 2028, following publication of our 2026-based SNPPs.

November 2025

We have implemented improvements to the way we estimate long-term international migration. For the first time, all aspects of these estimates are produced using administrative data and they no longer rely on survey data, as described in our Updating our methods to improve EU and British migration statistics blog post.

Following user engagement, we published provisional UK population estimates for mid-2025. We recommend using these more up-to-date estimates when a UK-only estimate is needed (such as for gross domestic product (GDP) per capita).

December 2025

We published 2021 estimates of the number of households at local authority level for England and Wales in our Admin-based household estimates for local authorities in England and Wales dataset. These estimates are based on administrative data (supported by survey data) and are official statistics in development. This year, we will develop these estimates, including producing a household size breakdown and providing estimates for more recent years.

Census 2021 data have now been linked to the ONS Longitudinal Study (LS) and are available through the Secure Research Service. These data include new variables, such as sexual orientation and veterans' status. The LS now spans 50 years (from 1971 to 2021) and includes data from a sample of 1.3 million people.

January 2026

The Population Statistics System Committee met, where they discussed the topic consultation and strategy and highlighted challenges, such as planning for inclusivity and relevance six years ahead.

We held a webinar to explain the latest statistics and developments in both births and deaths statistics. We now publish our Deaths registered weekly in England and Wales dashboard, which clearly presents the latest mortality trends and provides access to the data that inform public health policy. We would welcome your feedback on the dashboard; please contact us at Health.data@ons.gov.uk.

February 2026

The Government Statistical Service (GSS) consultation on the ethnicity harmonised standard closed on 4 February 2026. We will begin analysing the responses and will publish a consultation update around 12 weeks after the consultation closing date.

The Office for National Statistics (ONS) Permanent Secretary outlined the priorities for the organisation in a letter to the UK Statistics Authority Interim Chair, published on 19 February 2026. These priorities include reducing our publications and committing to putting quality over quantity. This letter also included confirmation that we will continue to run the Annual Population Survey (APS) at a lower level of resourcing.

A joint population statistics roundtable was held with the ONS, Office for Statistics Regulation (OSR), and Royal Statistical Society (RSS) to bring together senior colleagues from across the statistical system and user community. The roundtable focused on important opportunities, methodological and other challenges, and population statistics user needs. This will inform the development of administrative and alternative data sources that will complement the 2031 Census, by the ONS, National Records of Scotland (NRS), and Northern Ireland Statistics and Research Agency (NISRA).

Professor Stephen Jivraj from University College London hosted an online event about the ONS LS and the Centre for Longitudinal Study Information and User Support (CeLSIUS) service, and gave examples of research using the 2021 linked data.

We published our Reason for international migration, international students update: February 2026 bulletin on 27 February 2026. Users can give feedback and views on our priorities, relating to analysis on reason for migration, by completing our Reason for international migration feedback form.

Winter 2026

• Our research into international temporary mobility (migrants who stay in the UK for less than 12 months) is going through external assurance processes; this review will help to develop the proof of concept for publishing initial estimates of international temporary mobility.

• We are requesting feedback on our annual veterans' publication; please complete our User feedback on UK Armed Forces veterans statistics for England and Wales publications form.

Spring 2026

• Our Population statistics system webinar on 12 March 2026 will give users a chance to hear more about our plans for the population statistical system.

• We plan to publish the next edition of our Electoral registration statistics, UK dataset, which will include data for the parliamentary constituencies used for the elections to the UK (Westminster) parliament; we are also in the process of resolving data quality issues, with the aim of including data for local authorities in subsequent releases.

• We are planning to publish our International migration research, progress update article, which will give an overview of progress on our research and information about our releases publishing in May 2026.

• We will be publishing a high-level response to the Census 2031 topic consultation, summarising the responses received.

• We will publish our National population projections: 2024-based bulletin in April 2026.

• We will publish our Long-term international migration estimates: year ending December 2025 on 21 May 2026.

• We will begin research into techniques for nowcasting deaths by date of occurrence; we hope this will allow us to report all-cause weekly deaths based on date of occurrence (actual date of death), rather than date of registration.

• We are developing new methods for estimating small area populations at Lower Super Output Area-level; we are planning a publication to gather feedback and help to evaluate these methods.

• We are continuing work to investigate additional administrative data sources and methods to improve our internal migration estimates, which forms an important part of the plans for improving our population estimates; we are aiming to publish a research report on this later in 2026.

• To make it easier for users to access and use our data and statistics, we are redesigning our website; insights from user research are invaluable for helping us create a website that works for everyone – please register your interest in participating in our user research.

Summer 2026

• The Office for Statistics Regulation (OSR) will publish its findings from the population estimates compliance check.

• We will publish 2025 mid-year population estimates for England and Wales; we will also confirm the timetable for publishing UK estimates.

• We will publish our annual births estimates for 2025 in May or June.

• We will publish our Admin-based veterans statistics for 2024, which will update on the previous data for 2023.

• We will publish the outputs from our Census 2031 topic consultation, including full, topic-level evaluation reports and our updated assessment of the content for Census 2031 in England and Wales.

• We will provide an update on our research into using administrative data to produce estimates of the population by country of birth and nationality.

Autumn 2026

• We will publish our long-term international migration (LTIM) estimates to the end of June 2026 on 26 November 2026.

• We will publish a provisional UK population estimate for mid-2026, which will take into account the latest LTIM estimates.