Five benefits of a four-day working week, according to the world's largest trial

four-day working week Commuters walk to work as subway workers strike for the third time in as many months, in central London, Wednesday, Nov. 3, 2010. Nearly every line on London's Underground subway network, which carries about 3 million passengers on a typical weekday, was either suspended or disrupted. Commuters fought their way on to packed buses, biked, or just walked to work. (AP Photo/Lefteris Pitarakis)
The benefits of a four-day working week included better physical and mental health, lower rates of burnout and maintained productivity, according to a trial. Photo: Lefteris Pitarakis/AP/Alamy

The world’s largest trial of a four-day week has come to an end with positive results. Of the 61 companies that entered the six-month trial, 56 have decided to continue with the new working pattern ⁠— and 18 have made it permanent.

Over 2,900 people took part in the six-month trial, which saw companies agree to give workers an extra day off with no cut to pay. The organisations that took part ⁠— which included different businesses from digital banking firms to a take-away ⁠— reported a range of benefits, from improved work-life balance and health to fewer sick days.

Both employees and employers benefited from the trial, which was run by the 4 Day Week Campaign and 4 Day Week Global. Companies rated their overall experience of the trials an average of 8.5 out of 10 and while hiring increased, absenteeism and sick days decreased. So what were the other key findings from the study?

Maintained productivity

Many organisations fear that productivity will drop if employees work fewer hours. However, the results of the trial suggest these concerns are unfounded. In fact, most companies involved said productivity was maintained.

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Company revenue barely changed during the trial period ⁠— even increasing marginally by 1.4% on average for the 23 organisations able to provide data.

Fewer sick days

Stress, burnout and the subsequent impact on people’s physical health have forced an increasing number of people to take sick leave. There were more working days lost to sickness absence in 2021 than at any time in the past decade, according to ONS data.

However, a four-day working week reduced the number of sick days taken by 65% as people were able to rest and recuperate on their extra day off.

Better physical and mental health

Although the trial only gave workers one extra day off, the results showed significant benefits on both physical and mental health.

Workers were able to use their day off for admin tasks, such as shopping, medical appointments or household tasks, which left their weekends free for resting, leisure and exercise.

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Professor Juliet Schor of Boston College, the lead researcher, said the results were stable across workplaces of different sizes ⁠— suggesting the four-day week could work for lots of types of organisations.

“We found that employees in non-profits and professional services had a larger average increase in time spent exercising, while those in construction and manufacturing enjoyed the largest reductions in burnout.”

Lower rates of stress and burnout

Reports of burnout among UK workers have reached record levels over the past year. Data compiled by Glassdoor, which studied more than 380,000 anonymous employee reviews between June 2021 and May 2022, found that negative discussion about burnout is on the up, increasing by 48%.

However, the results of the trial suggest a shorter working week may help tackle the growing problem. Behavioural scientist and CEO of 4 Day Week Global, Dr Dale Whelehan, said the four-day week was particularly beneficial for women.

“While both men and women benefit from a four-day week, women’s experience is generally better. This is the case for burnout, life and job satisfaction, mental health and reduced commuting time,” said Whelehan.

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“Encouragingly, the burden of non-work duties appears to be balancing out, with more men taking on a greater share of housework and childcare.”

During the four-day week trial, six in 10 workers said they found an increased ability to combine their work with caring for a child, relative or person with additional needs.

Better sleep

The reduced stress and burnout, along with the opportunity to spend more time exercising, also helped to improve people’s sleep too. While one sleepless night is unlikely to impact your work, studies suggest that poor sleep in the long-term can affect your performance, attendance, mood, ability to make decisions and overall health.

However, employees who took part in the trial reported fewer problems with sleep, potentially due to the increased opportunities to relax and unwind.

The 4 Day Week Campaign is lobbying the government to introduce legislation to give workers the right to request a four-day work pattern.

Co-founder and managing director of 4 Day Week Global, Charlotte Lockhart, said: “Our team is delighted to be expanding the arguments in favour of a 4 day week today with this new world-class academic research. We look forward to adding our Australasian pilot results to this data set in the coming weeks and our European, South African, Brazilian and North American results in the coming months.”

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