A recent study by the UK’s Grantham Research Institute on Climate Change and the Environment at Imperial College London estimated that 50,391 excess heat-related deaths occurred across 854 European cities during summer 2026.
Excess mortality refers to the difference between the actual number of deaths and the number expected under normal conditions. Europe experienced its most intense heat in many years, with Spain, Portugal, France, Italy and Greece among the countries hardest hit.
The cities covered by the study have a combined population of around 173 million, with people aged over 85 recording the highest mortality rates.
Northern Europe recorded the lowest mortality rates, while the highest were reported in the south. Malta, Italy, Hungary and Croatia were the most affected countries.
Temperatures across Europe were generally around 2.5°C higher than they would have been without human-caused global warming. Researchers estimate that climate change linked to human activity accounted for 65% of the fatalities, or around 32,600 deaths.
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Around one-third of the total occurred between June 17 and July 1, when Europe’s average daily temperature was 5.3°C above normal.
By comparison, the number of heat-related excess deaths fell by nearly half in 2025, to around 24,500.
The research covered only urban populations, representing around 40% of the total population of the 30 countries included in the study.
The researchers said the final figure is expected to be higher and that summer 2026 will likely prove to be the deadliest heat-related summer in European history.
