Temperature-related mortality trends in England and Wales

Data from the Office for National Statistics (ONS) regarding temperature-related mortality in England and Wales shows a significant disparity between cold and heat-related deaths. Over a 37-year period, there were 149,042 deaths associated with the coldest 2.5% of days, compared to 42,133 deaths during the hottest 2.5% of days.

Recent trends indicate the gap between cold and heat-related mortality is narrowing. In May and June 2026, an estimated 2,877 heat-related deaths occurred in England and Wales, representing approximately 6% of the total hot-day fatalities recorded over the nearly four-decade period.

Regional analysis shows that the South East experienced the highest number of climate-related deaths, with London recording the highest number of deaths specifically linked to hot days. Experts suggest the urban heat island effect, alongside factors such as overcrowding and high living costs, may contribute to these figures in major cities.