Excess deaths caused by heatwaves in England ‘almost double’ so far this year

UKHSA estimates 2,877 fatalities during heatwaves in May and June, almost twice that recorded in 2025 season

England is on track to record its highest ever number of heat-related deaths this summer after the UK Health Security Agency (UKHSA) announced that an estimated 2,877 people had died in the May and June heatwaves.

The record was set in 2022 with 2,985 deaths, and August, traditionally the hottest month, is yet to arrive. The health secretary, Yvette Cooper, said: “My thoughts are with all those who have lost loved ones as a result of the long and intense heatwaves.”

The UKHSA analysis estimated there were 753 deaths in the the heatwave from 24 to 27 May and a further 2,124 between 21 and 28 June. The total is almost double the figure for the whole summer in 2025.

The UKHSA estimate is based on recorded deaths. It calculates the excess mortality during the heatwaves when compared with mortality levels at similar times of the year that did not experience heatwaves. The figures are similar to an estimate published on 13 July that used a different method, based on data showing the link between heat and deaths in the past.

Heatwaves are made more intense and more likely by the fossil-fuel-driven climate crisis; the heatwave that affected western Europe at the end of June was the most severe and widespread ever . The heat in 2027 will be exacerbated by a looming super El Niño weather system and temperatures will continue to rise until carbon emissions are cut to net zero.

“The new figures highlight the significant danger that very hot weather can pose to people’s health,” said Dr Ross Thompson, principal environmental public health scientist at UKHSA. “As the climate becomes warmer, we can expect periods of hot weather to become longer, more frequent and more extreme. That’s why it’s vital that individuals, communities and systems are prepared to deal with higher temperatures, and to ensure those most vulnerable are protected.

Cooper said this summer’s heat was having “an increasingly serious impact on the health of thousands of people, and on the pressures facing our NHS too. My heartfelt thanks go to the NHS staff, care workers and emergency responders who have worked tirelessly through these exceptionally busy and challenging months to protect and care for people affected by the heat.”

Some ambulance services reported a record number of calls during the heatwaves.

During the June heatwave in England a new high temperature for the month, of 38C, was recorded at Lingwood, Norfolk, while the 31.5C recorded at Kew Gardens in May was a new record for that month.

Dr Garyfallos Konstantinoudis, of Imperial College London and co-author of the 13 July study, said: “The UKHSA’s analysis provides clear, tragic confirmation of the significant health impact these heatwaves had across England and Wales. Extended periods of extreme heat place immense strain on the human body.

“Let’s not forget that behind these numbers are real people who died too soon,” he said. “We must take urgent action to adapt our homes, care settings, and infrastructure, while doubling down on global efforts to reach net zero and stop temperatures rising further.”

There may be small changes to the UKHSA estimate in the coming months when full death records are available.