Heat Deaths in England Are Catching Up to Cold Deaths
On 26 August 2026, the Office for National Statistics (ONS) — the UK's official statistics body — released a report called "Climate-related mortality, England and Wales: 1988 to 2025." It found that 109,000 deaths in England over that 37-year period were linked to the coldest days. But the more surprising finding: deaths linked to the hottest days have been going up in recent years, and the gap between heat and cold deaths is shrinking. The Guardian
The report looked at deaths from all causes that happened during the hottest and coldest 2.5% of days, using daily average temperatures across English regions and Wales. The data accounts for COVID-19, breaks down deaths by age, sex, and cause, and includes guidance on how to interpret the findings. ONS
London is the area hit hardest by heat. The ONS found the capital had the highest number of deaths linked to the hottest temperatures in England. An earlier ONS study had already shown that when temperatures go above 29°C, the risk of dying in London is three times higher than at comfortable temperatures. The lowest risk of dying in England was between 9 and 22°C; in Wales, between 8 and 20°C. ONS
The pattern shows up clearly in earlier data too. A previous ONS report estimated 51,670 heat-associated deaths in England and 2,186 in Wales between 1988 and 2022 (on days above 25°C). When warm and cold effects were combined, there were 555,103 fewer deaths overall from 2001 to 2020, averaging 27,755 fewer deaths per year. The heat-periods in 2022 alone caused an estimated 4,507 deaths in England and Wales. That year, dementia and Alzheimer's disease were the leading underlying causes of excess deaths during heat-periods. ONS
The 2026 report confirms what recent summers have already shown. The UK Health Security Agency estimated on 30 July 2026 that 2,877 people died in the May and June 2026 heatwaves in England, nearly double the total for the entire summer of 2025. London's ambulance service handled 25,000 more calls in summer 2026 than the summer before, surpassing even the busiest period during the Covid-19 pandemic. The Guardian | Greater London Authority
Hospital emergency departments across England had their busiest period ever in summer 2026, with nearly 2.5 million visits each month from May through July, partly driven by the heat. A nurses' union warned in August that staff were collapsing during shifts under "inhumane and impossible" conditions caused by extreme heat. BBC | The Guardian
This trend goes beyond England. The World Health Organization reported in May that heat-related deaths across its European region had risen by more than 30% over the past 20 years. Across the continent, at least 35,000 excess deaths occurred during the 2026 summer, based on figures that covered only about half of European countries. The Guardian | The Guardian
Heat-related deaths are not new, but they are getting worse. Excess deaths during heat-periods in England were documented from 2016 onward, with the 2016 summer alone producing an estimated 908 excess deaths per Public Health England. The new ONS data, by extending the series through 2025 and improving its methods, confirms the direction: cold still causes more deaths overall, but heat is catching up faster. An aging population, the growing number of people with dementia, and buildings and roads not designed for long stretches of high temperatures all make the problem worse. ONS
The broader context here is that England's buildings, healthcare system, and emergency services were designed for a mild climate. The data now tracks a system under growing strain — think of a house built to stay warm in winter, struggling to cope when it turns into an oven in summer. London's high number of heat deaths, ambulance call volumes beyond pandemic levels, and nurses collapsing on shift all point to gaps that statistics can measure but cannot fix on their own. The narrowing gap between heat and cold deaths is not a prediction about the future. It is something already happening through 2025, visible in both the numbers and the real-world pressure on hospitals and emergency services.
