14 of the 15 companies chose to continue with the four-day week after the trial ended.

Not a single one reported a drop in productivity.

Six companies saw productivity actually increase.

The rest said output stayed roughly the same.

These firms operated across a wide range of industries, from property management to publishing and health technology, which makes the findings harder to dismiss as a niche experiment.

When people say you need to work more to be productive and that having brutally long workweeks is the only way to keep things going.... they are spreading misinformation. You can definitely criticize this study for perhaps tending to select people and corporations who are open to a four day workweek, but this is still serious evidence that a four day workweek is at the very least equally productive as a longer workweek for corporations and that needs to be written on billboards with huge flashing lights so we can get that fact through everyones' heads. The data doesn't support working your life away being productive, which makes being effectively forced to do so all the more cruel and arbitrary.

https://www.nature.com/articles/s41599-026-07536-x

This research set out to investigate the new 100:80:100 version of the 4DWW, to better understand the motivations behind companies who have trialled it, identify the key themes associated with it, and ascertain its potential to improve the balance between the work and non- work lives of employees. A blended approach, using both transformational and servant leadership to understand the implementation of the 100:80:100 model, identified enhanced productivity (SDG8), improved work/life balance (SDG3), the ability to be able to use the 100:80:100 model as a recruitment/retention tool, and the capability to accommodate diverse schedules where leaders were able to redesign the workweek to better support the changing needs of workers and workflow.

Another article about the same study https://phys.org/news/2026-05-australian-companies-fourday-week.html

Other evidence in support of the Four Day Workweek being better for everybody.

https://www.ukri.org/who-we-are/how-we-are-doing/research-outcomes-and-impact/esrc/a-four-day-working-week-improves-mental-and-physical-health/

https://www.reuters.com/world/europe/four-day-work-week-boosts-spanish-workers-health-pilot-programme-shows-2023-10-17/

https://sloanreview.mit.edu/article/how-far-reaching-could-the-four-day-workweek-become/

https://hbr.org/2026/04/whats-stopping-the-4-day-workweek

https://www.uts.edu.au/case-studies/mythbusting-four-day-work-week

https://www.theguardian.com/technology/2019/nov/04/microsoft-japan-four-day-work-week-productivity