Four-day working weeks improve mental health and do not affect profits, study finds

Some companies have permanently moved to a four-day week after the six-month trial

Productivity appears to rise when people work four-day weeks. Photo: Alamy Stock

Four-day working weeks do not result in any drop-off in revenue or profits, while employees are happier, less stressed and sleep better, a major study has found.

In one of the largest trials yet, 41 companies in sectors including services, consulting, energy and childcare implemented a four-day week in Germany. The trial began in February 2024 and ran for six months.

Prof Julia Backmann, research lead for the project, organised by the 4 Day Week Global organisation, said that firms showed “the same output” even after staff shifted to a four-day week.

“Profit as well as revenue remained stable or relatively stable compared to the same months in the previous year,” she said. “We have a significant decrease in time [worked] but the same outcome, so the conclusion was that there were productivity gains.”

The research, results of which were reported on Friday, involved more than 600 interviews with management and staff before, during and at the end of the trial period. Data was collected through surveys, while heart rates and sleeping patterns were recorded.

There were also control groups who continued to work five days a week, with their results compared against those of staff who had shifted to a four-day week.

“Life satisfaction increased significantly compared to the start of the trial,” Prof Backmann said. “At the end people were more satisfied because of an increase with life and life quality.”

Self-reported findings that stress levels were down and sleeping improved were backed up by data from the digital recording devices.

“For the four-day week employees compared to the five-day control group, they experienced less stress measured in minutes of stress, they experienced more activity measures by the amount of steps they took. They also slept longer compared to the five-day week control group,” said Prof Backmann, who works at the University of Münster.

Will four-day working weeks become the norm?

At the end of the study, 73 per cent of organisations taking part opted to continue with a four-day week, with about half each implementing it permanently and the other half continuing with the trial. Around 20 per cent have moved back to a five-day week, while seven per cent are evaluating the results and are yet to make a decision.

Prof Backmann said that companies may implement a four-day week to become more attractive to potential employees, to improve employee health, to improve productivity or to become more “future-oriented”.

“More than 70 per cent of organisations said they found it easier to attract new talent, especially skilled workers,” she added.

Another of the project’s researchers, Carsten Meier, said that implementing a four-day week required careful planning to realise productivity gains through, for example, finding new methods to collaborate, hold meetings or have “focus times”.

“The challenge of doing the four-day week is that it’s hard work – it’s not something you suddenly switch on,” he said.

In recent years there has been growing interest from companies and employees in the four-day week, with advocates saying that staff can do just as much in four days as in five because they work more efficiently.

Work for many has already been transformed in the post-Covid world by the increased acceptance of working from home, at least in some sectors.

Mr Meier, whose management consultancy, Intraprenör, was a partner in the trials in Germany, said that a four-day week could be a way of making some roles that cannot be carried out from home more attractive.

What is the global picture?

In the Emirates the four-day week is gaining traction, with Sharjah having introduced it for government employees in January 2022.

A government-led pilot programme has been testing the four-day week in the public sector in Dubai, while some UAE private companies have also introduced a four-day week. However, some employees in the country are still required to work a six-day week.

The Greek government introduced a law in July that allowed companies in some sectors to compel staff to work six days a week, with the government saying that the rule was needed to promote growth following an exodus of workers in the wake of the country’s economic crisis, and to support increasing numbers of pensioners.

By contrast, a law that came into force in Belgium in 2022 gives employees the right to request a four-day week, albeit without a reduction in hours.

Four-day week pilots have been held in several countries, including in the UK, where in July the findings of a trial at South Cambridgeshire District Council, a local authority in south-east England, were published.

One of the researchers involved, Brendan Burchell, professor in the social sciences at the University of Cambridge, said that the study was one of the most comprehensive ever, as the authority had “very good data” going back a number of years for 24 key performance indicators (KPIs), such as how it was collecting rent or answering the telephone. Of the KPIs, 11 improved, 11 stayed about the same and two got worse.

“That's the best evidence anyone in the world had got in terms of productivity of the four-day week,” he said.

As well as appearing to improve productivity, the four-day week is popular with employees, Prof Burchell said, with only one to three per cent preferring five days.

“People love doing a four-day week,” he said. “They feel they're better able to recuperate. If you measure anxiety and depression, people's mental health has improved.”

He said that people working a four-day week were not having to “run around like flies” at work but were, for example, having shorter meetings and procrastinating less.

“Some people who've never, ever thought about productivity start coming up with great ideas about how they could change the way they work,” he said.

Can a four-day week really work in every industry?

A large-scale trial of 61 British companies, also organised with 4 Day Week Global and carried out by a range of academics including Prof Burchell, took place in 2022 and reported its results early last year.

After the trial, 56 of the companies said they would continue with the four-day week, with 18 saying the change was permanent.

However, Prof Burchell indicated that companies in sectors such as retail or construction may have found it harder to implement a four-day week. Four days a week may be more difficult for roles such as looking after the elderly, he said.

Also, a four-day week trial in the town of Kerteminde in Denmark reportedly found an increase in fatigue, blamed on staff working longer days.