Rapid early assessment by the UK Health Security Agency (UKHSA) has estimated that there were 2,877 heat-associated deaths in the May and June heatwaves. This is almost double the figure reported for 2025.
There were an estimated 753 deaths associated with the May heatwave between 24 and 27 May and another 2,124 in the June heatwave between 21 and 28 June.
These figures are still interim.
The June heatwave was only the second time a red heat-health alert has been issued and both May and June Met Office monthly temperature records for England with 31.5C recorded at Kew Gardens on 26 May and 37.7C recorded at Lingwood, Norfolk on 26 June.
Based on current data, the UKHSA says it is likely that 2026 could see the highest number of heat-associated deaths on record, surpassing the 2,985 recorded in 2022.
Dr Ross Thompson, Principal Environmental Public Health Scientist at UKHSA and author of the report, said: "These figures highlight the significant danger that very hot weather can pose to people’s health. This is particularly true for those who are more vulnerable including older adults and people with underlying medical conditions.
"While the figures are interim, they suggest that, if we experience more periods of hot weather this summer, we could see the highest number of heat-associated deaths on record.
"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 to the heat are protected."
Health and Social Care Secretary, Yvette Cooper, said: "The sweltering heat has had a serious impact this summer on people’s health and on our NHS.
"For many years, we have been used to winter pressures in our NHS and the need to support those who are vulnerable in the coldest weather. But now we are seeing the summer heat have an increasingly serious impact on the health of thousands of people, and on the pressures facing our NHS too.
"My thoughts are with all those who have lost loved ones as a result of the long and intense heatwaves in recent months. And 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.
"As we move through the summer, it is so important for people to be able to look out for their health and help those who are more vulnerable to the hot conditions. Please don’t hesitate to seek help if you’re worried about your own wellbeing, or anyone else’s. A little care could make a lifesaving difference."
