Sociologists Ran A 4-Day Workweek Trial – And The Results Speak For Themselves

Higher job satisfaction, better physical health, improved mental health, enhanced work performance, fewer burnouts, lower levels of fatigue, and a reduction of sleep problems are just some of the benefits of four-day workweeks identified in a new study.

The standard Monday-to-Friday workweek is not based on any inherent necessity or a natural cycle, but historical and social convention. Originating during the Industrial Revolution and later codified in the early 20th century to accommodate labor demands and religious days, the five-day workweek has persisted into the 21st century more out of tradition than logic. 

As the world of work changes, many organizations are now dabbling with the idea of introducing a four-day week. This can be achieved by having an extra “weekend” day off or by simply reducing work hours each workday.

To test the benefits of this structure, sociologists at Boston College ran a 6-month trial of the four-day workweek involving 2,896 employees across 141 organizations in Australia, Canada, New Zealand, the UK, Ireland, and the US. They gathered data before and after the trials using surveys that asked about employees' work satisfaction and indicators of their health, including things like burnout, mental and physical health, and so on. This was then compared to data on 285 employees at 12 companies who did not take part in the four-day week trial.

Here’s what they found: people who experienced a four-day workweek reported larger reductions in burnout, plus improvements in job satisfaction and mental health, compared with those at companies that maintained a five-day workweek. 

Even employees who had 1–4-hour and 5–7-hour reductions in their workweek also benefited, with a reduced number of sleeping problems and levels of fatigue, as well as improved individual work ability.

The key was that employees' salaries remained the same, despite cutting back on their hours. But profit-driven employers need not be discouraged – other trials have suggested that productivity doesn’t decline with reduced hours. In fact, many companies find that employees get just as much done, if not more, when working four days instead of five.

“Traditionally, time spent working is used as a proxy for productivity, when in fact better-rested and healthier people can be more productive in less time. The four-day week model in this study enhanced work ability, reduced sleep problems, and decreased fatigue—all of which contributed to the positive outcomes. While the study centred on a four-day week, the broader implication is clear: flexible and potentially individualised working arrangements can deliver similar benefits,” Associate Professor Paula O’Kane, an expert in human resources from the University of Otago, who wasn’t involved in the new study, said in a statement.

“Interestingly, many organisations who participated in the trial were not-for-profits, who often offer flexibility in lieu of higher salaries, perhaps the for-profit sector can learn from them,” she added.

This new research is far from the first piece of evidence to highlight the benefit of four-day work weeks.  A growing body of evidence suggests that cutting back on hours doesn’t just benefit employee well-being, but it can also boost productivity, or at least maintain it. 

Artificial intelligence is radically shifting the way we work, automating repetitive tasks and allowing humans to focus on higher-level, creative, and strategic work (at least, that’s the theory). In this new landscape, clinging onto the five-day workweek appears to be increasingly irrational and outdated. If we have an evidence-backed way to support a healthier, more productive, and more balanced approach to work, why not embrace the change?

The study is published in the journal Nature Human Behaviour.