Employees taking part in four-day week trials are spending their extra day off on personal tasks, volunteering, and in some cases moonlighting in other jobs, according to new research.
A team of researchers from the University of Birmingham found that while many used the additional day for rest, chores or creative pursuits, some were taking on freelance work or launching side businesses. It’s raising concerns among some managers about the potential for conflict with their main job or for staff to become overloaded.
The study was conducted by Dr Mengyi Xu, Dr Daniel Wheatley, Dr Holly Birkett and Professor Tony Dobbins at Birmingham Business School, with the findings presented at the British Sociological Association’s Work, Employment and Society conference in Manchester last week. It focused on participants in the so-called 100:80:100 model, in which staff retain 100 percent of pay while working 80 percent of the time and maintaining 100 percent productivity.
How employees spend the fifth day
Dr Wheatley told delegates that the research found varied use of the additional day off, including leisure activities, family responsibilities and professional development. He said that “in addition to using the time for leisure, chores, caring responsibilities, and engaging in education or community and voluntary work, several interviewees reported engaging in side hustles and other paid employment during their fifth day”.
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He noted that in a minority of cases, employers had concerns about how this might affect productivity. “Tensions were present in a small number of instances, with employer representatives and leaders reflecting on the risk their staff’s main job suffers due to work overload.”
One manager interviewed as part of the research said: “People will start their own business with the extra time. They’ll start their own social media channel – that is fine as long as it doesn’t affect your work. But the data shows that when people have too much going on, their work does suffer in general.”
Another manager said: “If you come in here knackered on Monday, this is the main gig, and if you’re going to jeopardise it, that’s your risk.”
Wellbeing gains outweigh risks
Despite these issues, the researchers found that both employers and employees reported overwhelmingly positive outcomes from the reduced working week.
“What really stood out was how employees valued having genuine ‘me time’,” said Dr Xu. “Parents with school-aged children especially described this as a completely new relief — finally being able to do something for themselves rather than constantly juggling work and childcare.”
One interviewee said: “I definitely notice a huge impact on my wellbeing; I feel a lot better. There’s more work life balance and it actually makes me a lot happier in my job as well. The impact is huge. I can’t really imagine going back to working five days. It feels like a whole different world.”
Younger workers most supportive
The research also pointed to generational differences in how the four-day week is perceived. One participant said: “The most supportive group of people on the four-day work-week are Gen Z and millennials. For the baby-boom generation, the four-day work-week is almost like taboo; it’s like shameful; it’s lazy.”
While the compressed schedule was seen as a benefit by most, some said it brought challenges, particularly around work intensity. One employee said: “It can be quite hard and tiring to adjust to when you’re burning through energy very quickly and time very quickly.”
Potential for broader social impact
Dr Wheatley said the findings supported a case for wider implementation of the four-day week across sectors. He said the model could benefit carers and others who need more flexibility, while also reducing environmental impacts by cutting commutes.
“The four-day working week offers substantial potential employee-organisation win-win outcomes, with wider societal benefits possible through improving communities and supporting reductions in inequalities and environmental impacts of economic activity,” he said.
The study involved 32 in-depth interviews with workers and managers from organisations trialling the 100:80:100 model. Participants reflected on both the benefits and the growing pains of making a compressed week the norm. A full report on the research has not yet been published, but the team said the early findings suggest lasting value in offering staff more autonomy over how they manage their time.
