Performance overview (April 2025 to March 2026)

Overview

The ONS faced significant challenges over the past year, including in relation to organisational leadership and culture, and the quality of statistics. The Authority Board and Cabinet Office jointly commissioned Sir Robert Devereux to examine the performance and culture of the organisation. Sir Robert published his recommendations in June 2025 and, in response, several changes were implemented to restore users’ confidence and focus on improving the quality of our statistics. The Public Administration and Constitutional Affairs Committee (PACAC) also commenced an Inquiry into the work of the Authority and its executive offices (ongoing at the time of writing).

Throughout the past year, despite the challenges we faced, we published 88.2% of our releases on time across a range of statistical topics. We also progressed digital modernisation and methods reform, and maintained our international leadership, particularly through global standards development. However, work in some areas was constrained by data and methodological pressures affecting specific economic series, resourcing gaps in analytical and interviewer roles, and the demands of running multiple transformation programmes in parallel. The pace and complexity associated with moving away from legacy surveys and platforms also placed strain on production.

The Devereux review provided clear direction on strengthening prioritisation, user engagement and internal accountability, which we used to inform actions to improve resilience, transparency and trustworthiness of our statistics. Our resulting work to narrow the scope of our portfolio to focus on improvement activity has been welcomed by many users, including our new transparent approach to communications and engagement. However, it should be noted that some prioritisation decisions have been difficult for users of some specific statistics. Whilst some users have recognised the prioritisation challenges and have welcomed the engagement, other users are, perhaps inevitably, disappointed with some prioritisation decisions and have been concerned about the resulting impact.

We have continued to listen to, and consult with, experts through our National Statistician’s advisory committees, which provide external challenge that strengthens the methodological rigour of our statistics. Following the completion of the monitoring period for the Inclusive Data Taskforce recommendations, we renewed the Chair and membership of the National Statistician’s Inclusive Data Advisory Committee and welcomed its advice and feedback on the development of GSS Harmonisation data standards and the 2031 Census consultations.

We have continued to engage with Parliament, including PACAC as it conducts its inquiry. During the year, we published Economic Statistics and Survey Improvement and Enhancement plans, reporting progress transparently on a quarterly basis while being clear about the challenges we have encountered and how we are responding across the breadth of our work. To support these improvement plans and invest in our core outputs, we paused lower priority activity, including concluding the Integrated Data Programme and refocusing analytical resources on critical priorities.

Further information can be found at Annex C 2025/26 Key Milestones.

Organisation and culture

We have implemented significant structural, cultural and governance change to strengthen leadership, improve capability and restore confidence.

In 2025, following the resignation of the then National Statistician, Professor Sir Ian Diamond, it was decided, at least temporarily, to split the role of the National Statistician. This was a recommendation in the Devereux review, dividing the role between a National Statistician and Permanent Secretary of the ONS. Darren Tierney was appointed Permanent Secretary in August 2025. Emma Rourke, Deputy National Statistician for Health, Population and Methods held the position of Acting National Statistician between May and December 2025. A recruitment campaign for the role of National Statistician is underway. Last autumn, Sir Robert Chote, stepped down as Chair of the Authority and Penny Young is currently Interim Chair until a permanent Chair is appointed.

Alongside, there has been an organisational restructuring to bring surveys, economic, population and social statistics, and corporate functions into clearer, more accountable groupings; and the National Statistician’s Office has been established to increase focus on system-wide statistical issues. Governance arrangements have been strengthened through weekly Executive Committee meetings, and the establishment of new decision-making sub-committees focused on people, strategic design, and performance and change.

Following the Devereux review, the ONS leadership capability has been strengthened with new appointments in key roles. James Benford joined the ONS in August 2025 as Director General for Surveys and Economic Statistics Group (SES). His priorities include leading the improvement plan for ONS economic statistics, ensuring they meet the highest standards of accuracy, transparency and public value. We have also made appointments to wider leadership roles including the Executive Director for Population, Census and Social Statistics, the Director of People and Places, the Director of Strategy and Change and the Director General for Digital, Data and Technology.

There has been an increased focus on transparency and more open engagement with staff, enabled through regular colleague forums, pulse surveys, and partnership working with Trade Unions, as well as the articulation of shared leadership values and the development of a People Plan. An agreement with unions on hybrid working has provided clarity and a more mature framework to support effective collaboration and productivity. Together, these changes mark a shift toward a more integrated, accountable and strategically aligned organisation, with greater emphasis on culture, capability and sustainable delivery.

Economic Statistics

Throughout 2025/26, we strengthened the quality, resilience and trustworthiness of the UK’s economic statistics, while continuing to manage a demanding programme of transformation. Core monthly outputs – including Gross Domestic Product (GDP), labour market statistics and the Consumer Prices Index (CPI) – were delivered consistently while strengthening assurance. We increased our focus on transparency and user communication recognising that this period is characterised by economic volatility, challenging survey response rates, increased use of administrative and alternative data, and necessary methodological change.

In June 2025, we published the Plan for Economic Statistics (ESP) and the Survey Improvement and Enhancement Plan (SIEP) to restore the quality of economic and population statistics. These formed part of the response to Sir Robert Devereux’s review of the ONS’s performance and culture and the Office Statistics Regulation’s (OSR) systemic review of economic statistics. Over two thirds of the milestones within the plans were delivered by the end of March 2026. Progress was supported by strengthened governance, clearer prioritisation, and the introduction of new quality review and data governance frameworks in response to the OSR’s recommendations. Progress depends on managing a set of interrelated risks over time, including specialist capacity in areas such as digital, data and methodology, the scale and sequencing of complex change, fiscal pressures, and competing demands such as Census 2031.

Given capacity constraints and the need to protect the quality of the most critical outputs, we prioritised key surveys and operational delivery. Following feedback from users, the Annual Population Survey continued to run, however in the short-term has a reduced survey boost in England, while we seek to address user needs in the longer term through labour market transformation.

We prioritised permanent interviewer recruitment and focused field capacity on the Living Costs and Food Survey (LCF) given its importance for GDP, prices and household disposable income statistics.

A significant milestone was the incorporation of grocery scanner data into CPI from February 2026 data onwards, covering around half of the UK grocery market. This represents a step change in coverage and quality, reduces reliance on legacy processes, and aligns UK consumer price statistics more closely with international best practice. Alongside this, targeted improvements to price collection and methodology – including expanded samples for selected components – reduced volatility and strengthened confidence in published inflation measures.

Labour market statistics remained central to public and policy debate. Confidence in the Labour Force Survey (LFS) continued to improve as response levels recovered to close to pre-pandemic levels following sustained survey improvements. We implemented all agreed major design changes to the Transformed Labour Force Survey (TLFS) and continued to work closely with users to prepare for the first evidence-led readiness assessment in July 2026 (further details are included in the next section).

Population, Census and Social Statistics

In January 2026 we brought together population statistics, social statistics and Census 2031 in a newly created group; Population, Census and Social Statistics (PCSS). The decision reflects the interconnected nature of the three areas, and the additional value we can gain from bringing them together. Census sits at the heart of our local statistics as well as underpinning our population statistics and household surveys. Bringing these areas together enables us to work more coherently, share expertise more effectively, and ultimately serve our users better.

During the year the group’s focus has been on improvements to outputs which have the greatest impact on decision making. We have moved away from reliance on survey data in our long-term international migration estimates, which now draw on administrative data. Domestic abuse estimates from the Crime Survey for England and Wales are now published as accredited official statistics and we have moved the ONS Local Service from beta to live.

During 2025/6, we have started preparations for Census 2031, following the Government’s decision in July 2025 to commission the Census in England and Wales. The commission of a census in 2031 followed the UK Statistics Authority Board’s endorsement of the Future Population and Migration Statistics (FPMS) recommendation, which built on extensive engagement with departments and wider users to set the strategic direction for a modernised population statistics system. We have published the Census 2031 Strategy and taken forward preparations for the 2027 Census Test, supported by early commercial engagement, capability building and active governance oversight.

Given the context of Census 2031, we have reviewed our approach to mid-year estimates. We will not move to the proposed new methods for mid-2025, instead following a continuous improvement model which supports improvements to quality. The Census remains the most reliable way to produce a comprehensive, high quality population snapshot, alongside continued investment in administrative data between censuses.

ONS has made significant improvements to how we produce migration statistics, making greater use of administrative data. In November 2025, we introduced new methods which removed our reliance on the International Passenger Survey (IPS), and now means our estimates are based on observed data, rather than intentions reported at ports and airports. This is the culmination of many years of development with the latest change for British Nationals, moving away from the IPS to use of DWP Registration and Population Interaction Database (RAPID) data for British nationals. At the same time, we also moved to use of Home Office Borders and Immigration (HOBI) data for EU nationals.

During this period, we strengthened crime statistics and analytical capability through methodological redevelopment and improved stakeholder engagement, particularly in surfacing the benefits and limitations of a variety of crime data sources. Key progress included publication of the ONS Centre for Crime and Justice’s Redevelopment of domestic abuse statistics: research update in May 2025 and gaining accreditation of the domestic abuse estimates from the Crime Survey for England and Wales in October 2025. 

In a drive to modernise collection methods, 2025 saw the launch of an updated, online Children’s Crime Survey, with the first results due for publication within the next few months, as well as a feasibility assessment for replicating elements of the face-to-face Crime Survey for England and Wales in an online capacity. A pilot survey was completed following a recommendation from an independent inquiry into Child Sex Abuse, and work will continue to create the framework for this to be rolled out at scale.

We have continued to evolve the ONS Local service, strengthening our support to Mayoral Strategic Authorities and focusing analysis and development work on prioritised user needs. We continued to support capability building with local stakeholders, delivering 37 workshops and webinars with attendance exceeding 600 stakeholders at some events. We published a range of outputs and new statistics, covering topics such as sectors and business dynamism, analysis on towns and high streets, and improved new statistics such as small area Gross Value Added and small area Gross Disposable Household Income. Building on feedback from the UK Statistics Assembly, we established a rural statistics working group and published updated Rural Urban Classification and corresponding analyses.

Explore Local Statistics, our digital dissemination service to find, compare and visualise statistics about places in the UK, transitioned from Beta to Live in April 2025. Throughout the year, we continued to increase the number of local indicators available on the platform and enriched its functionalities, improving access to local data and supporting engagement with local leaders. We also strengthened support to Mayoral Combined Authorities, with future development of the tool shaped by user need and resourcing priorities.

Responsive analysis

We produced timely analysis across economic and social domains on priority issues for policymakers and Parliament, including work on energy intensive industries, public service productivity, and analysis supporting labour market, trade and migration releases. While responsiveness was sometimes constrained by resource pressures and transformation activity, it remained a core strength. We are developing new methods to adjust LFS non-response bias using tax data, we published analysis of mortality by sexual orientation contributing to the LGBT+ Health Evidence Review, and we began analysis of over 1,400 responses to the Ethnicity Harmonisation Consultation. We continued to innovate and deliver impactful analysis on key societal and economic issues – for example through creating a unique linked data set we were able to provide the first official estimates of the long-term economic impact of motherhood.

Data, tools and innovation

We made progress in strengthening integrated data capability, modernising digital infrastructure and accelerating innovation across statistical production, improving analytical tools for the ONS through re-using assets from the Integrated Data Programme.

Data Growth and Operations colleagues received positive endorsement from the National Data Guardian of the National Health Service (NHS) and the Secretary of State for the Department of Health and Social Care (DHSC) in support of the ONS further linking health and economic data.

Our data strategy was extended to December 2027, which enabled us to strengthen the governance of the data estate across the organisation. We progressed innovation in statistical methods, including the first operational use of a Large Language Model for occupation coding in the Annual Survey of Hours and Earnings (ASHE), reducing processing time by around 50%. Digital transformation continued through migration of key business surveys to modern platforms, improvements to software engineering practices, and the introduction of new digital tools, improving usability, insight and production efficiency. This reflects our ongoing commitment to transform business surveys and reduce our legacy estate over the next five years.  We continued to look at the use of Artificial Intelligence (AI)  with the in-house development of a ClassifAI application and collaboration with the IMF on their StatGPT tool explained in the Permanent Secretary’s Foreword above.  Going forward we will be refreshing the ONS Digital and Data Strategy to set out the ONS’s longer-term direction for technology, data and the incorporation of AI.

We have made, and continue to make, improvements in response to a more recent “Limited” Data Governance audit through the creation of a new Data Governance Office and a business improvement roadmap targeting clearer accountability of data domains and a suite of tooling which supports greater understanding and usability of our data estate.