The UK results published in February 2023 were not the first coordinated evidence. In December 2022, 4 Day Week Global reported the outcomes of its pilots in the United States, Ireland and other countries. The cohort was smaller than the UK’s, but its message rhymes: staff were strongly in favour, companies rated the experience highly, and revenue rose during the trial window.
Who took part
The December 2022 report covered 33 companies and about 903 employees who had completed a six-month pilot beginning in February 2022. As with the UK, these were volunteer firms following a reduced-hours model at full pay, with preparation support and an expectation that output would be maintained.
That volunteer design is both the strength and the limit of the finding. These firms show what prepared, motivated organisations can achieve. They do not show what happens when a shorter week is imposed on an unprepared workplace with no workload redesign.
Revenue, ratings and the wish to continue
Revenue rose by about 8.1% during the trial window. Companies rated their overall experience at roughly 9 out of 10. Most strikingly, 97% of employees said they wanted to continue with a four-day week, and no responding company planned to return to five days at the point of reporting.
Read the revenue figure carefully. It is a within-trial rise reported by participating firms, not a controlled comparison against similar firms that stayed on five days. Growing firms are more likely to volunteer for high-profile pilots, and revenue can rise for reasons that have nothing to do with hours. The defensible claim is not “cut hours and revenue rises 8%.” It is “revenue did not fall; in this cohort it rose.”
The 97% figure is easier to interpret. Staff who have experienced a real reduction in hours rarely want to hand it back. That has a direct management implication: a pilot creates an expectation. If you run one, agree the decision criteria before you start and communicate them plainly, because ending a popular pilot badly costs more trust than never starting it.
How staff said their performance changed
Employees’ self-rated performance rose from about 7.2 to 7.8 out of 10 between the start and end of the pilots in report summaries. Self-ratings are not objective output measures, and Day5Group would not advise any board to rest a decision on them alone. They are still useful alongside revenue, customer and quality data because they cut against the simplest objection — that staff themselves felt they were getting less done.
The wider pattern across these pilots was that staff reported lower stress and better work-life balance while rating their own productivity the same or better. Iceland’s earlier public-sector trials pointed the same way: 2,500 public workers moved from 40 hours toward 35–36 hours with no pay cut, and productivity and service provision were maintained or improved in most workplaces while stress and burnout fell.
What to copy, and what not to
Copy the preparation. Firms in these pilots spent time before launch cutting meetings, clarifying priorities and agreeing how success would be judged. Copy the measurement: revenue and ratings mattered because firms tracked people outcomes and business outcomes together.
Do not copy the headline as a forecast. Your result will depend on your demand pattern, your coverage model and whether you genuinely remove work. A firm that keeps the same workload, the same meetings and the same inbox expectations in four days should expect intensity to rise — and the wellbeing gains to shrink.
If you are planning a pilot in spring 2023, the US and Ireland results give you a reasonable prior: prepared firms can hold output, staff will likely want to keep the day, and the commercial risk is manageable when customer floors are agreed in advance. Prove it in your own context, with your own numbers.
Sources
- 4 Day Week Global, US, Ireland and international pilot results, December 2022 — reported via International Workplace, December 2022: https://www.internationalworkplace.com/community-zone/news/four-day-week-pioneering-pilot-program-a-huge-success-new-research-reveals
- Autonomy and Alda, Iceland shorter working week trials 2015–2019, reported 2021: https://phys.org/news/2021-07-shorter-week-boost-productivity-burnout.html
Day5Group is a consultancy that assists in the transition to a 4 day work week. More about Day5Group · All blog articles