Extreme summer heatwaves in the UK caused direct economic output losses of at least £4.4 billion ($5.95 billion) due to declining worker productivity and infrastructure disruptions, according to research released Wednesday by think tank Verdant.
The report updated earlier estimates to account for four distinct heatwaves recorded between May and late July 2026.
May's early heatwave resulted in roughly £500 million in damage, while peak temperature episodes in June and July led to losses of £2.36 billion and £1.5 billion, respectively.
Analysts' calculations showed that each one-degree Celsius rise above 30 degrees Celsius in Europe reduced average hourly worker output by 3%.
Researchers projected cumulative annual UK productivity losses reaching £25.6 billion by 2030 if extreme heat trends continue at the current pace.
To mitigate future losses, the think tank recommended establishing a national maximum working temperature, introducing a heat insurance scheme and expanding investments in urban cooling infrastructure.
