A study found that reducing working hours to four days a week without wage cuts positively affects workers' physical and mental health and overall job satisfaction. Reducing working hours can enhance employee welfare without hindering corporations' productivity.
A research team led by professors Juliet Schor and Wen Fan from the sociology department at Boston College in the United States noted on the 22nd that after testing a four-day workweek on 2,896 workers for about six months, they confirmed that employee well-being and corporate productivity can coexist through reduced working hours. The research findings were published that day in the international journal 'Nature Human Behaviour.'
The researchers evaluated burnout, job satisfaction, mental health, and physical health scores for workers at 141 corporations across the U.S., the U.K., Ireland, Australia, New Zealand, and Canada before and after implementing the four-day workweek. They also compared these scores with 285 workers from 12 other corporations that maintained a five-day workweek during the same period.
Those who worked on the four-day schedule saw their average weekly working hours decrease from 39.2 hours to 34.0 hours, a reduction of about five hours. The analysis revealed that workers on the four-day workweek experienced decreased burnout and increased job satisfaction. Burnout scores decreased from 2.83 to 2.38 out of 5, while job satisfaction increased from 7.07 to 7.59 out of 10.
Both mental and physical health improved. The mental health score increased from 2.93 to 3.32 out of 5, while the physical health score improved from 3.01 to 3.29 out of 5. In contrast, the control group that continued with the five-day workweek showed no statistically significant changes in burnout, job satisfaction, mental health, or physical health scores.
The research team revealed that individuals whose weekly working hours were reduced by more than eight hours showed significant improvements in every aspect. This indicates that mental and physical health increased linearly with the extent of the reduction in working hours.
The researchers analyzed that the positive effects of reduced working hours are due to increased job performance, as less working time leads to a decrease in sleep disorders and fatigue. Consequently, quality of life improved along with job performance.
The research team explained that organizational changes positively affect individual workers, enhancing their quality of life and job performance, suggesting the need for organizations to redesign work methods, such as implementing a 'four-day workweek with maintained wages.'
Previous studies on the four-day workweek were mostly limited to the public sector in Nordic countries or were merely observational studies. However, this research is based on analyzing actual results from multinational private corporations that changed their working hours.
Yun Woosang, the director of Bright Mind Hospital, stated that the research presents empirical evidence suggesting that 'the introduction of a four-day workweek does not undermine productivity' and emphasized that the significance lies in the fact that the restructuring of the entire organization, not just the reduction of individual working hours, has prompted changes in perceptions and behaviors among all members.
Director Yun explained that this research indicates a departure from the existing stereotype that 'ideal workers are those who work long hours,' suggesting that it is possible to achieve higher job efficiency and welfare with fewer hours through the four-day workweek.
References
Nature Human Behaviour (2025), DOI: https://doi.org/10.1038/s41562-025-02259-6