More than 50,000 people are estimated to have died across Europe as a result of this summer’s record-breaking heatwaves, according to research.
In the UK alone, researchers estimate there were 4,354 excess deaths this summer.
The number of excess deaths across Europe is double the number recorded in 2025 and it is also far higher than the previous record of 29,000 deaths. This was recorded in 2022 when the continent also endured exceptionally high temperatures, with the mercury hitting 40 degrees celsius for the first time in the UK.
According to the Met Office the UK saw its hottest ever summer this year with five widespread heatwaves and 40 days where the temperature was above 30 degrees celsius. Mainland Europe experienced its third hottest summer, with temperatures particularly high in the south and west.
Researchers from Imperial College, London and the London School of Hygiene and Tropical Medicine (LSHTM) looked at 854 urban areas in 30 countries across Europe. Using temperature records and modelling based on the relationship between heat and mortality they estimated the number of heat-related deaths that occurred between June and August.
They said findings from previous years’ excess heat mortality modelling matched official figures released later by national health authorities.
Because the study only looked at urban areas – making up 40 per cent of the population of the countries studied – researchers believe the number of deaths is likely to be an underestimate.
According to the study, published in Nature Health, southern and western Europe were hardest hit. Italy experienced the highest number of excess deaths (13,303), followed by France (7,268), Spain (6,824), Germany (6,340) then the UK.
There were an estimated 22,000 deaths among those aged 85 and over but researchers pointed out that an estimated 6,000 people under the age of 65 are also likely to have died as a result of the heat.
Around a third of the deaths took place in late June, when average temperatures across Europe were more than 5°C above what would be expected during this time of year. Researchers say in early summer people were less likely to have acclimatised to the sweltering weather. This period was marked by both extremely high humidity and unusually high night-time temperatures, making it difficult for people to cool down.
Researchers also estimated that more than two thirds of the total excess deaths were attributable to climate change. Across the continent as a whole Europe was an average 2.9°C higher than would have been expected. However, in some places temperatures were as much as 12°C higher.
Dr Clair Barnes, extreme weather and climate change researcher at Imperial College, said extreme heat was having a severe impact on public health.
“It is yet another reminder both of the imperative of rolling out targeted interventions to protect those who are most vulnerable to this increasingly extreme heat, and of the growing need to rapidly transition away from fossil fuels to slow the pace of change and limit future warming.”
Dr Pierre Masselot, assistant professor of statistics and epidemiology at LSHTM and one of the study’s authors, said “climate change is everybody’s problem”.
“It is not just hot regions that are suffering any more with some parts of Western and Northern Europe experiencing extreme heat and historically high health burden. And the whole population is affected, as shown by the significant death toll among younger age groups.
“It is becoming increasingly clear our cities are poorly adapted to rising heat, and it is critical we improve our efforts towards adaptation. This means cooling the cities through more green spaces and less pollution, and providing health care for affected populations.”
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