All 17 organisations that took part in the UK’s latest four-day working week trial have opted to continue with reduced working hours, as research shows improvements in staff wellbeing, mental health and overall satisfaction.
The six-month pilot, organised by the not-for-profit 4 Day Week Foundation and monitored by researchers at Boston College in the US, saw nearly 1,000 employees across a range of sectors reduce their working hours without a drop in pay.
Following the trial’s conclusion, 12 companies have adopted a permanent four-day week, while five have introduced a nine-day fortnight.
The participants included both small and large employers, from organisations with fewer than five staff to those with more than 400. Among them were Bron Afon Community Housing, the British Society for Immunology, the National Union of Students and the Scottish Sports Association.
Burnout Drops, Satisfaction Rises
According to post-trial data published by the 4 Day Week Foundation, the benefits to staff were notable:
- 62% reported a reduction in how often they experienced burnout
- 41% said their mental health improved
- 45% reported feeling more satisfied with life overall
“With greater knowledge, expertise and experience of what it takes to successfully implement a four-day week, we’re really pleased to see such a high success rate. People are happier, businesses are thriving and there’s no turning back,” the foundation’s campaign director, Joe Ryle, said.
Employer Confidence in Performance
Alan Brunt, chief executive of affordable home provider Bron Afon Community Housing, which has 420 employees, said the organisation would continue operating on a reduced-hours model.
“We’ve closely monitored our performance and customer satisfaction. We’re happy with the results so far and will continue to make sure we’re delivering for our customers,” he said, adding that he expects most companies to adopt a four-day week over the next decade.
The 4 Day Week Foundation has so far accredited more than 235 UK companies that have permanently adopted the model, covering over 6,000 workers. While the idea has previously been dismissed by some policymakers — described by the former Conservative government as “part-time work for full-time pay” — the current Labour administration has taken a more open stance.
Deputy Prime Minister Angela Rayner has previously said that a four-day week is “no threat to the economy”, though no formal provision for it exists in the current Employment Rights Bill.
Wellbeing Gains and Business Benefits
The trial adds to a growing body of evidence suggesting that a shorter workweek, when implemented well, can lead to measurable improvements in employee wellbeing, as well as benefits for employers in the form of productivity, retention and engagement.
Participants in earlier UK trials also reported positive outcomes. In a broader pilot run in 2022, 92% of companies continued with the four-day week beyond the trial, citing improved staff morale and reductions in absenteeism. Workers reported less stress and better work-life balance, while many companies noted increased efficiency and smoother workflows.
According to the 4 Day Week Foundation, successful implementation typically involves a combination of operational review, open consultation with staff and tailored planning to ensure service levels are maintained. In many cases, companies have used the transition to review meetings, processes and time usage to identify and eliminate inefficiencies.
Implications for Workplace Wellbeing
For employers considering a four-day week, the potential wellbeing gains are clear. Reducing working hours without reducing pay addresses key drivers of stress and burnout — particularly overwork and lack of recovery time — while signalling a strong commitment to employee health.
With nearly two-thirds of workers in the latest trial reporting reduced burnout, the four-day week presents a meaningful strategy for organisations focused on preventing mental health decline, improving work-life balance and retaining talent in a tight labour market.
The 2025 National Pilot, now underway and open to new organisations, continues to test the model across a wider range of industries and settings. The 4 Day Week Foundation offers structured support and peer learning for participating employers.