Preface

The summer of 2026, defined by record-breaking heat, wildfires, and drought, serves as a critical wake-up call for UK leadership. By early August, the nation entered its fifth heatwave of the season, resulting in dozens of homes destroyed by fires and millions receiving risk alerts. This extreme weather disrupted transport, strained hospitals, and threatened food production, hitting the most vulnerable populations hardest. Prime Minister Andy Burnham has acknowledged that government strategy has not kept pace with a changing world. Adaptation must move from the margins to mainstream decision-making, as heat risk now poses a permanent threat to public health, emergency services, and economic productivity.

Summary

The unprecedented summer of 2026 has fundamentally changed the national conversation on heat risk. Although the challenge has been documented for over a decade, governance remains poor compared to other hazards like flooding. Flooding benefits from established strategies, lead institutions, and ministerial accountability, whereas heat risk remains one of the least governed climate threats despite being the deadliest to health. The National Heat Risk Commission was formed in March 2026 to drive action across all four nations, aiming to bridge the gap between plentiful recommendations and absent delivery. The Commission frames heat as a national security risk requiring a preventative, whole-society response to mitigate harm before emergencies arise.

The challenge: the UK is unprepared for extreme heat

Extreme heat reached unprecedented levels in 2026, with temperatures of at least 35°C recorded every month from May to August. This coincided with drought conditions affecting all of Wales and two-thirds of England, leading to over 1,000 wildfires. During the June heatwave, more than 1,000 schools were disrupted and critical incidents were declared across healthcare settings. The human toll was severe, with an estimated 2,877 deaths linked to the May and June heatwaves alone. Nearly nine million residents reported taking exceptional measures to cope, such as sleeping in alternative locations or taking unpaid leave. Economic costs are estimated at over £4.4 billion for the period between May and July 2026, with the June heatwave alone causing losses of up to £2.36 billion and 24 million lost working hours.

The National Heat Risk Commission

As the UK’s deadliest climate-related health risk, heat requires urgent attention to identify barriers to progress and accelerate action. The Commission envisions a resilient nation where public services function reliably and homes remain cool. Chaired by Emma Howard Boyd, the Commission provides independent expertise and strategy across the four nations. Operating from March 2026 to December 2027, the body intends to publish a major report in summer 2027 to inform the Fourth National Adaptation Programme (NAP4). Its role is to facilitate mobilisation and coordination rather than deliver programmes or set regulations.

From existing recommendations to future action

The report outlines 10 key recommendations to strengthen heat resilience. Governance reforms include aligning strategic risk assessment processes, such as the National Risk Register and UK Climate Change Risk Assessment, and publishing a national heat resilience strategy with clear ministerial accountability. Strategic authorities should be given statutory climate and nature duties to empower local action.

Regarding people and communities, governments must ensure public services like schools, hospitals, and prisons remain adequately cooled. Heat-health alerts require improvement to reflect humidity and better reach at-risk groups. Protections for the most vulnerable are prioritised, including the implementation of Awaab’s Law to address indoor overheating in social housing by November 2026. Infrastructure recommendations focus on harnessing green and blue infrastructure as cost-effective cooling and enforcing stronger design standards for buildings and transport. Economic actions include strengthening workplace protections, such as setting maximum workplace temperatures, and improving the evidence base through better monitoring of indoor temperatures and heat-related morbidity.

Call for evidence

The Commission has published a Call for Evidence to gather insights from organisations across the UK. This first phase focuses on the impacts of heat, successful interventions, and remaining evidence gaps. Information gathered will help determine the Commission’s focus areas and test the framing set out in this report. A second phase will later hear directly from individuals to ensure a comprehensive understanding of the risk.

Looking ahead

The current political context reinforces the need for a preventative state that acts early to reduce future costs. Existing legislative priorities, such as the Railways Bill, Clean Water Bill, and the 10-Year Capital Plan for Health and Social Care, offer immediate opportunities to embed heat resilience into long-term decisions. The Commission aims to bring stakeholders together to focus attention on these challenges and identify the actions needed to build a more heat-resilient UK.