Have some studies shown the shift to daylight saving time increases fatal car crashes?

Multiple studies have shown an increase in deadly vehicle crashes just after the shift to daylight saving time. Still, one study found it was offset by a decrease in pedestrian and bicyclist deaths, while another study found no effect.

A 2020 study in the journal Current Biology that analyzed more than 700,000 fatal crashes found a roughly 6% rise during the workweek after clocks “spring forward.” A 2016 study of crashes published in the American Economic Journal estimated the shift caused more than 30 deaths annually from 2002 to 2011.

However, a 2025 study by the Insurance Institute for Highway Safety found the annual increase in vehicle passenger deaths was offset by a similar decrease in pedestrian and bicyclist deaths. A 2010 study in the Journal of Environmental and Public Health found no increase in fatalaccidents from the switch to and from daylight saving time.