Two years after the first large four-day-week pilots reported, the follow-up data has arrived, and it permits a rare thing in work-policy debates: a mostly clear answer. Roughly two-thirds of companies that trialled a compressed schedule retained it permanently, and the pattern in the results is consistent enough to describe without hedging.
The headline numbers
Across published trials, the median firm held output approximately flat — some up, some down, most within a few points — while reported burnout fell sharply and voluntary turnover dropped by double digits. Revenue per employee was essentially unchanged. In other words: the productivity panic was overwrought, and the productivity paradise was oversold.
- Output: roughly flat across most adopting firms
- Turnover and sick days: meaningfully down
- Recruitment advantage: substantial, and growing in tight labour markets
Where it worked, and where it did not
The pattern is the interesting part. Compressed schedules succeeded overwhelmingly in knowledge work with flexible outputs — software, design, professional services, public administration. They struggled in operations with fixed coverage requirements: customer support, healthcare, manufacturing lines. The firms that succeeded there did it by hiring to cover the gap, which is why their stories are about costs rather than miracles.
The three honest caveats
First, selection bias: firms that volunteer for trials are unusually well-managed, and badly-run companies should not expect schedule changes to fix them. Second, measurement: “output” is easy to fake in a survey and hard to fake in a P&L; the trials with hard numbers show smaller effects than the surveys do. Third, the five-day week's ghost: many “four-day” firms quietly run five-day cultures with one fewer meeting day, and the employees notice.
For individuals weighing an offer from a four-day employer, the evidence suggests taking it seriously — the retention numbers imply people who make that choice tend not to reverse it. For managers considering it, the data's lesson is to fix the meeting load first; the compressed week succeeds where time-waste has already been pruned, and fails where it merely compresses the waste.