Does work time reduction improve workers' well-being? Evidence from global four-day workweek trials

Time spent on the job is a fundamental aspect of working conditions that influences many facets of individuals’ lives. We study how an organisation-wide four-day workweek intervention—with no reduction in pay—affects workers’ well-being. Participating organisations undergo pre-trial work reorganisation to improve efficiency and collaboration, followed by a 6-month four-day workweek trial. Based on pre- and post-trial data from 2,896 employees in 141 organisations, we find that the trial leads to improvements in multiple measures of well-being, including burnout, job satisfaction, mental health, and physical health—a pattern not observed in 12 control companies. Both company-level and individual-level reductions in hours predict well-being gains, with larger individual-level (though not company-level) reductions predicting greater improvements in well-being. Mediation analysis identifies three factors that significantly contribute to the relationship between reduced hours and increased well-being: improvements in self-reported work ability, reductions in sleep problems, and decreased fatigue levels.