The Labour Force Survey (LFS) operational lessons learned review identified a number of actions to strengthen operational oversight, governance and assurance. While the operational incident affecting the allocation of telephone interviewers to the LFS had a minimal impact on headline labour market estimates, it identified a small but noticeable impact on estimates of average hours and, consequently, total actual hours worked.
We have acted on the review's findings through a structured improvement plan and are implementing the recommendations across our telephone operations. This has included strengthening governance, assurance and performance monitoring arrangements to reduce the risk of similar issues occurring in future. The number of achieved responses to the LFS has been increasing since the incident and are expected to return to pre-pandemic levels in the coming few weeks.
This recovery in performance is being supported by a broader drive to increase the size of our face-to-face field community. The size of this increased from 833 in June to 876 in early September, achieving our minimum target size of 875 we set at the beginning of our recovery plan. Further increases in the field community are expected in the coming weeks.
As recommended by the lessons learned report and as indicated in the July Surveys and Economic Statistics Improvement Plan (SESIP) update, we are also looking more broadly across our social survey operations to ensure that the lessons learned are widely embedded. Further information on progress against the review's recommendations and wider social survey recovery activity will be provided in the October SESIP Plan update.
The report was finalised in August and is published in full below:
Background and context
The Office for National Statistics (ONS) commissioned an operational lessons learned review following an incident affecting Labour Force Survey (LFS) data collection.
The LFS is one of the UK’s most important social surveys, providing information on employment, unemployment and economic inactivity. The ONS is running the LFS alongside the Transformed Labour Force Survey (TLFS) as part of the testing and transition to the new survey.
The ONS has publicly recognised that running both surveys over a prolonged period is costly and complex. It has placed continuing pressure on resources, operational capacity and organisational attention. The ONS has had to balance recovery of the LFS and the quality of its outputs with delivery of a major transformation programme. This has created complex operating conditions and reduced operational flexibility. While this wider context did not directly cause the incident, it shaped the operational environment in which it occurred. The ONS is working towards full transition to the TLFS in 2027.
The review was commissioned to establish what happened, understand the factors that contributed to the incident, identify lessons learned, and recommend actions to strengthen operational performance. Evidence was gathered through interviews with colleagues in operational and management functions, supported by documentary evidence, management information and operational data, where available.
The review focused on operational delivery arrangements and did not examine survey methodology, statistical estimation, weighting, published outputs or individual performance.
What happened and why?
The review assessed an operational incident affecting Labour Force Survey (LFS) data collection between May and June 2026. During this period, achieved household interviews for LFS Waves 2 to 5 were approximately 2,180 lower than expected. The review found that 6,590 interviews were achieved compared with around 8,770 that would typically have been expected during an equivalent six-week period.
The review did not identify a single root cause. Instead, the incident arose from a combination of reduced operational capacity, increased operational demand and weaknesses in the controls used to assess, monitor and escalate the cumulative impact of change across the operation. Together, these factors created a mismatch between the interviewer resource available, and the level of activity required to deliver the LFS as planned.
The evidence suggests that decisions were made to reduce telephone interviewer capacity based on management information indicating that surplus capacity existed at that point in time. The review subsequently identified limitations in this information and found that it did not provide sufficient assurance that capacity could be reduced without wider impacts on operational performance. Additional interviewer capacity was also affected through agency leavers, internal moves, retirements and natural attrition.
At the same time, a new telephone inbound transfer process was introduced to support the Transformed Labour Force Survey (TLFS). This process required resource from the existing telephone interviewer workforce, reducing the interviewer hours available to support LFS interviewing activity. While the process may have delivered intended benefits for the TLFS, the extent of its impact on LFS interview volumes was not fully assessed or evidenced at the time.
The review concluded that the cumulative impact of these changes was not fully reflected in the information provided to decision-makers until LFS performance had already begun to deteriorate.
What the review found
The incident was not attributable to a single decision, team or individual. Rather, it resulted from the interaction of operational and organisational factors during a period of significant operational change. Six thematic findings emerged, which together, highlight key lessons that must be learnt to strengthen operational control and reduce the risk of future incidents.
Governance and oversight
Finding
Governance and assurance arrangements did not consistently provide sufficient visibility of operational risks, dependencies and trade-offs before significant operational changes were implemented.
Lesson learned
Governance should be strengthened to ensure significant operational changes have assurance arrangements that provide appropriate challenge, visibility of risks, and confidence that operational impacts have been fully assessed before implementation.
Resource planning and management
Finding
The review found that resource planning and management arrangements did not consistently provide assurance that sufficient capacity existed to maintain operational delivery while absorbing operational change and responding to emerging pressures. Resource decisions were not always supported by a complete understanding of cumulative operational demand, competing priorities and the resilience required to manage operational risk.
Lesson learned
Resource decisions should be informed by a clear understanding of current and future demand, operational priorities, workforce availability, and clear thresholds and performance measures.
Monitoring and management information
Finding
The review identified weaknesses in operational monitoring and the use of management information. Relevant data existed across the operation but was not consistently integrated or interpreted in a way that enabled emerging risks to be identified and addressed at an early stage. Performance measures, resource requirements and escalation triggers were not always clearly defined, reducing visibility of developing operational pressures.
Lesson learned
Effective operational oversight requires integrated, timely and trusted management information, alongside clear performance expectations and monitoring arrangements.
Escalation and accountability
Finding
The review found mixed evidence regarding how operational concerns raised before and during the incident were considered and acted upon. Ownership, accountability and escalation routes were not always sufficiently clear, and some escalation activity appeared dependent on individual judgement, suggesting a weakness in the system controls.
Lesson learned
Accountability, ownership and escalation routes should be clearly defined so that emerging risks can be identified, escalated and addressed consistently.
Operational expertise and communication
Finding
The review found that operational expertise was not always fully incorporated into decision-making. Evidence indicated that communication between operational, management and support functions did not consistently provide a shared understanding of operational impacts, resource pressures and implementation risks. Opportunities to identify and address emerging concerns may therefore have been missed.
Lesson learned
Operational expertise should be systematically incorporated into decision-making, supported by open communication, constructive challenge and collaboration across teams.
Operational resilience and maturity
Finding
The incident occurred within a wider context of organisational change, workforce pressures and competing priorities. While these factors were not identified as the direct cause of the incident, the review found that they reduced operational flexibility and resilience, limiting capacity to identify, challenge and respond proactively to emerging risks.
Lesson learned
Periods of operational change require sufficient resilience, capacity, controls and oversight to ensure emerging pressures can be absorbed without adversely affecting survey delivery.
Impact
The incident had a measurable impact on survey performance. Achieved household interviews for Labour Force Survey (LFS) Waves 2 to 5 were lower than expected throughout the affected period, resulting in approximately 2,180 fewer achieved interviews than would typically have been expected.
Analysis published in the Labour Force Survey quality update: July 2026 indicates the incident had a minimal impact on headline labour market estimates but suggests a small but noticeable impact on the estimates of average hours and, consequently, total actual hours worked.
The review also identified scope to strengthen the early identification and escalation of impacts on interview volumes. Stronger challenge, earlier escalation, improved monitoring or additional assurance may have enabled earlier intervention. While it is not possible to conclude that any individual action would have prevented the incident, the findings suggest that earlier action could have supported the identification and subsequent mitigation of emerging risks before their impact became material.
Immediate management response
Once the issue was identified, a range of mitigating actions were implemented by Social Surveys Telephone and Ports Collection (SSTPC) management to improve performance and strengthen operational oversight. These actions included enabling concurrent outbound Labour Force Survey (LFS) and inbound Transformed Labour Force Survey (TLFS) calling to maximise available operational capacity, enhanced performance monitoring, daily operational review meetings, strengthened management reporting, additional workforce planning activity, and recruitment measures to increase available capacity.
The Director of Social Surveys also implemented an Operational Performance Assurance Group that meets twice weekly and focuses on operational performance, current risks and emerging challenges. This has been introduced to strengthen Social Surveys Directorate’s (SSD) ability to be more proactive in identifying and managing issues coherently, and the principles and operating model underpinning this approach will also be adopted by SSD’s Operations Board going forward.
Survey performance has improved following implementation of these actions, with achieved interviews having increased from 913 at the lowest-performing point during the May to June 2026 incident period to 1,240 in the most recent cohort examined by the review. While this represents a positive improvement, survey performance had not fully returned to previous levels. This is partly because operational changes take time to translate into improved survey performance, with impacts typically taking around three weeks to become visible in achieved interviews for cohorts.
Actions implemented in response to the incident remain in place, and work is ongoing to strengthen longer-term workforce planning and recruitment. At the same time, further analysis is being undertaken to understand interviewer shift patterns and optimise resource deployment, while management information continues to be quality assured to ensure decisions are based on the best available evidence. Performance sustainability and pace of recovery will continue to be assessed.
Looking forward
This review focused specifically on the Labour Force Survey (LFS) and Telephone Operations within Social Surveys Telephone and Ports Collection (SSTPC) Division and therefore has reached no conclusion about whether the themes apply elsewhere. It is however prudent to evaluate where lessons can be shared and risks mitigated across the Operation.
The review therefore recommends a broader assessment of survey operations across Social Surveys Directorate (SSD) to develop a clearer understanding of operational performance, identify systemic risks, assess organisational resilience, and share good practice across survey delivery functions. Undertaking this work will help inform decisions on any further steps needed, beyond the LFS, to strengthen the resilience and effectiveness of operations across social surveys.
The review proposes that particular attention should be given to operational governance and assurance, operational change management, management information and performance reporting, resource and capacity management, and operational resilience. The aim would be to establish a clearer operational baseline, strengthen assurance and support the development of a more consistent operating model across social survey operations.
Alongside this, SSD should continue to foster a culture of constructive challenge and professional curiosity. This includes creating opportunities and an environment for colleagues at all levels to question assumptions, raise concerns and test emerging risks, helping ensure that potential issues are identified and understood at the earliest opportunity.
Forward plan
The Social Surveys Directorate (SSD) intends to develop a single plan to respond to the review. It will set out the improvements needed, who is responsible, when actions should be completed and how progress will be checked. The aim is to strengthen how SSD manages its surveys, including resource planning, performance monitoring, escalation, accountability and resilience. This single plan will be linked to the wider Directorate Social Survey Strategy to maintain coherence in recovery and sustainability work.
The first stage will assess how well survey operations are currently working across SSD. It will identify shared risks, links between different areas and differences in operational controls. It will also consider where common standards are needed and whether improvements made after the Labour Force Survey (LFS) incident could benefit other surveys and the wider operation.
The immediate priority is to begin this assessment and turn the review findings into clear actions. Progress will be managed through existing governance arrangements. SSD will continue to oversee the actions already taken or recommended following the LFS incident, while identifying the areas of greatest operational risk.
This work will help to provide an initial assessment of the current strengths and weaknesses of SSD’s survey operations. This in turn will inform an Operational Maturity Assessment, which will enable the Directorate to clearly see which strengths should be protected and where further improvement and investment are most needed as it carries on with its journey of continuous improvement.
SSD will need to balance this improvement work in line with broader Office for National Statistics (ONS) operational and change priorities. The work must have sufficient people, time and funding to succeed. If other activity needs to be paused, delayed or given a lower priority, those decisions will be made explicitly through established governance arrangements. A timetable for the wider improvement work will be agreed once the initial assessment is complete.
Afterword
I welcome the findings and recommendations set out in this report. While the review has identified important lessons, it has also highlighted the professionalism, commitment and expertise that exist across Social Surveys Telephone and Ports Collection (SSTPC). The actions already implemented, together with the recommendations arising from the review, provide a strong foundation for strengthening survey operations and supporting the continued delivery of high-quality social surveys.
This incident has highlighted opportunities to strengthen how we manage operational change and risk. By drawing on operational expertise, encouraging constructive challenge and learning from experience, we can continue to build resilience and improve our readiness for future challenges.
I am grateful to everyone who contributed to this review and to colleagues who continue to support the delivery of our social surveys.
Dr Alex Lambert OBE
Director of Social Surveys
Office for National Statistics
Acknowledgements
ONS internal reviewers
Carla Bushell, Laurie Hughes, Jack Challinor-Jones
ONS internal assurer
Stewart McBride
External reviewers
Darren Morgan (Economic Statistics Centre of Excellence), Steve Whatson (Home Office)