France, Netherlands and Belgium record 3,700 excess deaths in heatwave

France, the Netherlands and Belgium recorded about 3,700 excess deaths during a June heatwave that pushed temperatures sharply higher across Western Europe and strained health systems, power supply and infrastructure. The mortality estimate covers roughly June 20 to June 28, and authorities warned the figure was preliminary and could climb as more data come in.

The Netherlands has already put a hard number on part of that toll. Dutch health authorities said the heatwave caused around 480 excess deaths, with the heaviest impact among people aged 80 and over and the highest rates in the eastern and southern regions. RIVM activated the National Heatwave Plan on June 18, and most Dutch provinces were placed under a code red extreme-heat alert from June 26.

France faced some of the most extreme conditions in the region. The European Commission said a second heat dome settled over Western Europe in June, and Reuters and NBC News reported that France broke its hottest-day record on June 24. Météo-France said the national average temperature reached 30.0 C that day, underscoring how quickly the heat moved from a seasonal warning into a nationwide crisis.

Belgium’s health ministry called the excess mortality unprecedented, while the country’s official meteorological institute described June as very hot in its climatological summary. Taken together with the Dutch and French data, the figures point to a death toll that is broader than heatstroke counts alone, since excess mortality captures older people and those whose underlying conditions worsen during prolonged heat.

The wider European context is already stark. WHO/Europe said on June 11 that heatwaves have become a recurring crisis, warning that more than 200,000 people died from heat across Europe over the previous four years and that nearly all of those deaths were preventable. It also said more than half of countries in the region still lack a comprehensive heat-health action plan.

The European Commission’s adaptation portal said the June event followed an unusually early and intense heatwave in May, with red-level health alerts issued in France, Germany, Spain, Switzerland, the United Kingdom and Luxembourg. For health officials, the lesson is increasingly operational: excess deaths are not an abstract metric, but the clearest measure of how far a heatwave has pushed hospitals, emergency planning and cooling systems past their limits.