["The Journal of Physiology, EarlyView. ", "\nAbstract figure legend Deaths of climbers and Sherpas on standard routes during spring climbing seasons 2007–2024 are shown. Most climbers (76.5%) died on summit day, whereas most Sherpas (82.2%) died during route preparation. The mortality during descent from the summit was higher amongst climbers than Sherpas (0.8% vs. 0.1%, P < 0.0001). The mean altitude of fatal incidents involving climbers was higher than those involving Sherpas (7970 ± 917 m vs. 6894 ± 1195 m, P = 0.0003).\n\n\n\n\n\n\n\n\n\nAbstract\nMount Everest is climbed by an increasing number of mountaineers. Although climbing techniques have changed in recent years, the impact on patterns of mortality is unclear. To compare mortality patterns from 1921 to 2006 with those from 2007 to 2024, we performed a retrospective observational study of mountaineers climbing Everest. We extracted data from the Himalayan Database and examined accounts of deaths. The overall mortality rate above base camp decreased from 1.4% to 0.7% (P < 0.001). From 2007 to 2024, the mean altitude of fatal incidents on the standard routes involving climbers was higher than those involving Sherpas (7970 ± 917 m vs. 6894 ± 1195 m, P = 0.0003). Most climbers (76.5%) died on summit day, whereas most Sherpas (82.2%) died during route preparation. Climber mortality during summit descent on the standard routes during spring 1982–2006 vs. 2007–2024 decreased from 3.0% to 0.8% (P < 0.0001). The spring summit descent mortality for 2007 to 2024 was higher amongst climbers than Sherpas (0.8% vs. 0.1%, P < 0.0001). Mortality rates have decreased on Everest, but further improvements in safety at extreme altitude may be possible.\n\n\n\n\n\n\n\n\n\nKey points\n\nClimbing techniques on Mount Everest have changed in recent years, which may impact patterns of mortality.\nOverall mortality rates from 1921 to 2006 vs. those from 2007 to 20024 decreased from 1.4% to 0.7%.\nMost climbers still die on summit day, but mortality rates during descent from the summit decreased from 3.0% to 0.8%.\nAbove 8000 m, there are less death involving falls or climbers separated from their group, but profound exhaustion and impaired consciousness are still frequent symptoms of those who died in this hypoxic environment.\nAwareness of the persistent patterns of mortality may help mountaineers avoid fatal situations.\n\n\n"]