Tackling planning delays and housing under-supply across England: Can inter-municipal cooperation between local planning authorities help?
Lead Research Organisation:
University of Southampton
Department Name: Sch of Geography & Environmental Sci
Abstract
There are significant and stubborn backlogs in the English planning system. Government statistics, which are known to under-estimate planning delays (Ball, 2011), show that less than half of development applications sent to local authorities in 2021 were determined on time (RTPI, 2022a), down from nearly 80% in the mid-2000s. A recent survey of architectural firms found that 47% had experienced delays of greater than six months; and 22% had cancelled projects as a result (RIBA, 2023). Just 40% of councils have up-to-date "Local Plans" for meeting future housing needs (Levelling Up Committee, 2023). And enforcement activity has declined by 30% since 2008 (RTPI, 2022a), risking more unregulated development that breaches quality or environmental standards.
There is a notable spatial dimension to these problems. Being a locally-run and "discretionary" system, English planning has long been accused of being a postcode lottery (BUILD Magazine, 2019; Local Architects Direct, 2021). But the last decade has seen new inter-regional disparities emerge, reflecting "the uneven geography of local government austerity" (Gray & Barford, 2018). Overall expenditure on planning declined by 43% between 2009 and 2021; but the reduction was 62% in the North East, where local fiscal capacity could not offset central cuts (RTPI, 2022a). Application processing speeds dropped by, on average, 31% between 2013-2022, but the North East and West Midlands saw far greater declines. And while most councils now struggle to recruit and retain graduate planning officers, the problem is most acute in rural authorities (LGA, 2022; RTPI, 2022b).
Planning delays contribute to multiple social and economic ills. Land-use regulations restrict housing supply (Gyourko & Molloy, 2015; Dawkins, forthcoming). Even if fully-justified to serve other policy objectives, this slows economic growth (e.g., by restricting the talent pool available for business expansion), inhibits productivity (through long commuting times), and creates or exacerbates spatial, demographic and inter-generational inequalities (Szumilo, 2019). And the problem is not only regulatory design, but also how swiftly and predictably regulations are implemented (Ball, et al., 2009; Ball, 2011). As the Home Builders Federation recently argued, "Chronic under-resourcing and under-staffing in local planning authorities is leading to discrepancies, administrative errors and delays for developers" (see Built Environment Committee, 2022).
Given the likely continuation of austerity, councils are looking to administrative innovation to reverse the decline in planning performance. Since 2008, at least 17 have merged their planning teams with one or more neighbour to provide a "shared service" across several authorities. This de-facto regionalization should generate scale economies, critical mass in specialist planning roles, and an enhanced employment "offer" - improving organizational performance and reducing delays. Further, to manage regional spillovers more strategically and provide more consistent regulations for developers, 32 councils have collaborated on "Joint" Local Plans, again aiming to boost housebuilding.
Using postcode-level planning data, we shall evaluate the separate and combined effects of these two "re-scaling" interventions - one organizational, the other policy-focused. Our key question is: does either form of "inter-municipal cooperation" reduce planning delays and increase housing supply? Our spatial regression discontinuity design enables robust comparison of geographically-proximate planning applications that, falling on either side of an administrative boundary, are differently processed by either "treated" (i.e., collaborating) or "controlled" councils. The results will provide timely evidence on whether this type of administrative innovation should be extended further, and on how local public services affect economic outcomes.
There is a notable spatial dimension to these problems. Being a locally-run and "discretionary" system, English planning has long been accused of being a postcode lottery (BUILD Magazine, 2019; Local Architects Direct, 2021). But the last decade has seen new inter-regional disparities emerge, reflecting "the uneven geography of local government austerity" (Gray & Barford, 2018). Overall expenditure on planning declined by 43% between 2009 and 2021; but the reduction was 62% in the North East, where local fiscal capacity could not offset central cuts (RTPI, 2022a). Application processing speeds dropped by, on average, 31% between 2013-2022, but the North East and West Midlands saw far greater declines. And while most councils now struggle to recruit and retain graduate planning officers, the problem is most acute in rural authorities (LGA, 2022; RTPI, 2022b).
Planning delays contribute to multiple social and economic ills. Land-use regulations restrict housing supply (Gyourko & Molloy, 2015; Dawkins, forthcoming). Even if fully-justified to serve other policy objectives, this slows economic growth (e.g., by restricting the talent pool available for business expansion), inhibits productivity (through long commuting times), and creates or exacerbates spatial, demographic and inter-generational inequalities (Szumilo, 2019). And the problem is not only regulatory design, but also how swiftly and predictably regulations are implemented (Ball, et al., 2009; Ball, 2011). As the Home Builders Federation recently argued, "Chronic under-resourcing and under-staffing in local planning authorities is leading to discrepancies, administrative errors and delays for developers" (see Built Environment Committee, 2022).
Given the likely continuation of austerity, councils are looking to administrative innovation to reverse the decline in planning performance. Since 2008, at least 17 have merged their planning teams with one or more neighbour to provide a "shared service" across several authorities. This de-facto regionalization should generate scale economies, critical mass in specialist planning roles, and an enhanced employment "offer" - improving organizational performance and reducing delays. Further, to manage regional spillovers more strategically and provide more consistent regulations for developers, 32 councils have collaborated on "Joint" Local Plans, again aiming to boost housebuilding.
Using postcode-level planning data, we shall evaluate the separate and combined effects of these two "re-scaling" interventions - one organizational, the other policy-focused. Our key question is: does either form of "inter-municipal cooperation" reduce planning delays and increase housing supply? Our spatial regression discontinuity design enables robust comparison of geographically-proximate planning applications that, falling on either side of an administrative boundary, are differently processed by either "treated" (i.e., collaborating) or "controlled" councils. The results will provide timely evidence on whether this type of administrative innovation should be extended further, and on how local public services affect economic outcomes.
| Description | Over the past ten months, we gathered and analyzed millions of planning applications from local councils across England to see whether combining neighboring planning departments-what we call "shared services"-helps reduce backlogs and speed up development decisions. Our findings tell a mixed story. Positive Cases: A few inter-municipal collaboration cases significantly reduced delays once they joined forces, likely because they pooled specialized expertise or introduced new processes that worked well across areas. Overall Negative Effect: Most councils, however, found that shared services made planning decisions slower, especially for smaller ("minor") applications. Merging teams created additional layers of coordination-for instance, agreeing budgets or aligning IT systems-which sometimes canceled out any benefits of sharing. Varied Local Conditions: The same reform produced different results depending on local factors like staffing levels, budget constraints, and the size or rural/urban nature of the region. This can help explain why some shared services improved performance while others did not. By pinpointing where and why shared services succeed or fall short, our research helps policymakers and planning authorities decide whether to adopt (or adjust) these reforms. Ultimately, a "one-size-fits-all" approach may not solve planning backlogs. Instead, each council may need to account for its unique circumstances when combining planning departments, aiming for practical coordination and resource-sharing that actually speeds decisions rather than slows them. |
| Exploitation Route | How the Outcomes Can Be Used and Drive Disparities Reductions: Identifying Effective Shared Services: Because our research shows mixed results-some councils benefit greatly while others see worsened delays-we can now help policymakers to analyze the success factors identified in the positive cases (e.g., integrated processes, stronger resource sharing) and apply them in areas with persistent backlogs or limited capacity. This ensures that smaller or under-resourced authorities are given a blueprint for improving service delivery without creating new administrative workload for little or no performance gain - something that councils tell us is really important to avoid. Targeting Councils Most in Need: By highlighting where shared services have failed to ease delays, our data helps direct resources (e.g., training, IT investment, staff support) to the councils with the greatest disparities in planning performance. In this way, the findings can reduce uneven outcomes by preventing "one-size-fits-all" reforms in places that lack the preconditions for success. Geographical Area & ITL Code: The research covers England local authorities (ITL Level 3). The impacts so far primarily affect English local authorities. Potential Uses by Others: Local Government: Councils across England can apply our methods and data-driven insights to identify their main bottlenecks and allocate resources more effectively-especially smaller or lower-capacity authorities in greatest need. Regional & National Policymakers: Agencies like the Royal Town Planning Institute (RTPI) and the Scottish Parliament's Local Government Committee can tailor reform proposals (e.g., strategic planning guidance or funding priorities) using our empirical results. Professional Training & Practice: training/consulting bodies such as the Planning Advisory Service (PAS) can use of findings. Disciplines Involved: Economic Geography/Urban Economics; Urban Planning; Public Administration/Public Policy; Quantitative/Data Science. |
| Sectors | Communities and Social Services/Policy |
| Title | England-wide Local Planning Applications Database & Causal Identification Analysis Model |
| Description | Description of the Research Dataset: We have constructed a large-scale micro-level database of planning applications spanning all Local Planning Authorities (LPAs) in England between 2002 and 2024. This dataset includes millions of records (eventually 30 million individual applications) and contains over 30 attributes per case, such as: Actual decision time vs. target decision time, Submission date and validation date, Consultation milestones, Application type (major, minor, etc.) and Final decision outcome. Causal-Identification Model: Spatial RDD & Difference-in-Discontinuities: We employ Regression Discontinuity Design (RDD)-particularly a spatial RDD-to isolate causal effects by comparing planning applications just inside vs. just outside boundaries of local authorities that adopt certain reforms (e.g., shared services). This is combined with a Difference-in-Discontinuities (DiDisc) approach to incorporate time-series elements and compare outcomes before and after policy implementation. These methods allow us to establish credible causal inferences on whether administrative reforms reduce planning delays, improve housing supply, or affect refusal rates. |
| Type Of Material | Data analysis technique |
| Year Produced | 2025 |
| Provided To Others? | No |
| Impact | The research is still in its early stages, and it is too soon to identify any notable impacts at this point. |
| Description | Project Partner: Oxford City Council |
| Organisation | Oxford City Council |
| Country | United Kingdom |
| Sector | Public |
| PI Contribution | We have briefed Oxford City Council's Planning Department on the range of econometric methods required to answer policy questions and evaluate planning reforms. We have also presented our initial results, and arranged a follow-up discussion with the OCC analysis team. And, at their request, we have provided a bespoke dataset to OCC for their own internal analysis - based on a subset of our whole dataset. |
| Collaborator Contribution | Oxford City Council Planning Department helped us co-design the initial grant, identify and interpret the data sources required to execute the analysis, and, latterly, have created additional opportunities for us to disseminate the preliminary results. In particular, through ongoing dialogue, we jointly identified factors that influence planning delays and potential strategies to streamline the decision-making process. OCC Planning Department also guided us through the workflow that they operate locally, and the various bottlenecks that influence performance (e.g., environmental reports from the Environment Agency). We also discussed data availability and interpretation, alternative hypotheses we might explore, and additional audiences for disseminating our results. |
| Impact | This is a cross-sector collaboration between academic social scientists and local government officials / qualified town planners. Our collaboration enables us to apply social scientific methods of causal identification to data originating from a real and highly complicated policy sector. |
| Start Year | 2024 |
| Description | Project Partner: Royal Town Planning Institute |
| Organisation | Royal Town Planning Institute RTPI |
| Country | United Kingdom |
| Sector | Charity/Non Profit |
| PI Contribution | We have briefed the Royal Town Planning Institute on the range of econometric methods required to evaluate planning reforms. We have shared insights on data sources available for the analysis of local government performance and organizational behaviour. And we have also presented our initial results and robustness tests. |
| Collaborator Contribution | The Royal Town Planning Institute inspired our project (particularly through its "Planning Agencies" report in 2022), and helped us co-design the initial grant application. The RTPI subsequently helped us to identify and interpret the data sources required to execute the analysis, and provided suggestions for extensions to our analysis and additional reforms we could evaluate using the same data in future projects. They have also committed to helping disseminate relevant empirical findings to serving and in-training planners. |
| Impact | This is a cross-sector collaboration between academic social scientists and the professional body for qualified town planners. Our collaboration enables us to apply social scientific methods of causal identification to data originating from a real and highly complicated policy sector. |
| Start Year | 2024 |
| Description | Briefing for Oxford City Council Planning Department |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Policymakers/politicians |
| Results and Impact | As part of our collaboration with Oxford City Council, we presented the initial results from our impact evaluation, answered questions from the council, and then discussed new hypotheses we could try and other kinds of reforms we could evaluate. We agreed to hold two further meetings - one with the data / analysis team in the council, and one with the heads of planning for all Oxfordshire councils (i.e., not just the city). These are scheduled for the spring (i.e., the next reporting window). |
| Year(s) Of Engagement Activity | 2025 |
| Description | Briefing for Oxford Civic Society |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | Local |
| Primary Audience | Third sector organisations |
| Results and Impact | Meeting requested by the Oxford Civic Society to discuss our initial research findings, especially in the context of current plans to merge local councils in Oxford/Oxfordshire. The aim of the Civic Society is to improve and inform public debate about the proposed changes. Based on our conversation, they now plan to schedule later this spring one or two talks - open to society members and the general public - to discuss our research evidence as it relates to the planned council changes. We will present our data and answer questions. |
| Year(s) Of Engagement Activity | 2025 |
| Description | Briefing for Royal Town Planning Institute |
| Form Of Engagement Activity | A talk or presentation |
| Part Of Official Scheme? | No |
| Geographic Reach | International |
| Primary Audience | Professional Practitioners |
| Results and Impact | As part of our collaboration with the Royal Town Planning Institute, we arranged a formal presentation of our initial results with the RTPI research management team. We presented our findings, answered questions, discussed some questions we had about data interpretation, and identified the next steps for our research agenda. We also discussed the recent changes to the Labour Government's planning policy / reforms, and their relevance for our current and future research. |
| Year(s) Of Engagement Activity | 2025 |
| Description | Dialogues with the Planning Advisory Service (PAS) |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Professional Practitioners |
| Results and Impact | Engagement Activity: Our research team held a detailed discussion with the Planning Advisory Service (PAS) to present interim findings on how inter-municipal or "shared services" in planning affect local decision timelines. The conversation aimed to solicit expert feedback from PAS, which regularly advises local authorities and policymakers, and to refine our data-driven approaches for diagnosing planning delays. Outcomes/Impacts: 1. Influencing Policymakers and Industry: PAS uses evidence-based insights to advise councils nationwide. By incorporating our preliminary findings into their guidance, PAS can shape local or regional policy decisions (e.g., by identifying planning bottlenecks or resource needs) and encourage data-driven administrative reforms. These discussions may also inform future policy reports or white papers that address planning capacity and performance, contributing to a broader national conversation on effective local government services. 2. Engaging Citizens and Businesses: Although the engagement itself primarily involved PAS professionals, the resulting guidance impacts everyday planning services-ultimately affecting citizens, community groups, and local businesses seeking timely planning determinations. By highlighting the potential disparity in how smaller or lower-resourced councils handle planning applications, this engagement offers actionable approaches to improve equity in service delivery. 3. Driving Reductions in Disparities: The insights shared with PAS focus on identifying where planning delays disproportionately affect certain areas or applicant types. In turn, PAS can help direct resources and best practices to councils facing the highest backlogs, lessening geographical disparities and improving overall service quality. 4. Geographical Area & UK ITL Code: Discussions covered local authorities across England (ITL Level 3). 5. Number and Name of Disciplines Involved: Economic Geography/Urban Economics; Public Administration/Public Policy; Quantitative/Data Science. |
| Year(s) Of Engagement Activity | 2025 |
| Description | Submission of Written Evidence on Local Planning Reforms to the Scottish Parliament's NPF4 Inquiry |
| Form Of Engagement Activity | A formal working group, expert panel or dialogue |
| Part Of Official Scheme? | No |
| Geographic Reach | National |
| Primary Audience | Policymakers/politicians |
| Results and Impact | Activity: We submitted a written evidence document to the Scottish Parliament's Local Government, Housing, and Planning Committee, offering insights from our England-based research that may inform implementation of the Fourth National Planning Framework (NPF4). The written submission addressed local authority capacity, administrative reforms (e.g., inter-municipal cooperation), and their relevance to Scotland's planning challenges. Intended Purpose: To share lessons learned on reducing planning backlogs and place-based disparities, based on "big data" analysis of local authority reforms in England. To contribute evidence on how structural or regulatory changes can affect planning performance-ultimately providing actionable suggestions for improving Scotland's spatial strategy and policy priorities under NPF4. Outcomes/Impacts: Influencing Policymakers: Our evidence may shape the Committee's ongoing reviews, potentially informing future policy proposals or guidance documents aimed at strengthening local planning capacity. Reducing Disparities: By highlighting how resource constraints worsen development delays-often hitting less advantaged areas hardest-the submission underscores the importance of targeted support for struggling local authorities. Geographical Area & UK ITL Code: This engagement took place in Scotland (ITL Level 1). Disciplines Involved: Urban & Regional Planning; Public Administration/Public Policy; Quantitative/Data Science. Through this written contribution, we aimed to help policymakers address critical capacity and performance issues in local planning, thereby advancing the broader goals of NPF4 and supporting more equitable outcomes in Scotland's built environment. |
| Year(s) Of Engagement Activity | 2025 |