Between June and December 2022, sixty-one companies in the United Kingdom took part in the largest pilot of a four-day working week at that time. About 2,900 employees moved to a reduced schedule with no loss of pay. The companies ranged from a fish-and-chip shop to software and marketing firms, and the results were studied by researchers from the universities of Cambridge and Boston College.
The headline result was striking. Of the sixty-one companies, fifty-six decided to continue the four-day week after the trial ended, and eighteen made the change permanently. Although employees worked one day less, the companies' revenue stayed broadly the same over the trial period. Moreover, the number of staff who left their jobs fell sharply compared with the same period a year earlier, and the number of sick days fell too.
However, the results need careful reading. The companies volunteered for the pilot; they were not chosen at random. A firm that expects a shorter week to work is more likely to sign up for one, and more likely to make it succeed. Therefore, the pilot shows that a four-day week can work in some companies, not that it would work in every company.
In addition, six months is a short time. Some benefits of a new routine fade when it stops being new, and some costs appear only later. Despite these limitations, the pilot shifted the debate. Before 2022, critics argued that a shorter week would simply mean less work done. As a result of trials like this one, the question has changed: it is now less whether a four-day week is possible than for whom, and on what terms.
For readers who write reports themselves, the pilot also offers a quieter lesson. A good report separates what the data show from what we would like them to show. Although the first is less exciting, it is the part that survives the next study.