When Alice Will and her team at Edinburgh-based food and drink marketing agency Lux decided to trial a four-day working week back in January 2020, they chose not to tell clients as a way of testing its effectiveness.

"If our clients don't notice, then that's a huge measure of whether it's working … none of our clients did, which was great," the co-founder told CNBC in a recent video interview.

That was one of the key performance indicators Lux used to measure the success of its trial, in addition to productivity. To keep up with client workloads, Lux implemented an alternate shift pattern with some people working Monday to Thursday, while other employees worked Tuesday to Friday.

The agency made the four-day week a permanent feature, writing it into employee contracts, from January 2022.

Since the agency first started the trial, Lux's profits have risen 30%, while productivity is up 24%. Lux used time-tracking software to measure productivity, finding that despite employees working fewer hours, the company was actually making more profit.

For Will, moving to a four-day week has demonstrated that "it's not about how many hours you put in … it's about focusing on outputs."

'Massive difference'

The concept of a four-day working week was considered pretty radical just a few years ago. However, in the wake of the Covid-19 pandemic, demand for this working model appears to have picked up.

What's more, there's clearly a historical precedent for this kind of revolutionary change to working hours, as Alex Soojung-Kim Pang, who wrote a book on productivity and shorter working hours ("Shorter: Work Better, Smarter and Less – Here's How"), pointed out in a report published in January.

In as early as 1922, the Ford Motor Company experimented with reducing the working week to five from six days, and it became permanent policy four years later in 1926. 

And while it's still only just taking off, the four-day working week has already seen success in trials. Iceland's long-running trial of shorter working hours between 2015 and 2019 was hailed as an "overwhelming success." The country rolled out a permanent plan for its public sector employees in 2021, and one report in the same year found 86% of Iceland's working population either work shorter weeks or will have the right to.

Big-name companies have also conducted smaller four-day week trials, with consumer goods giant Unilever testing it out in New Zealand, and Microsoft trying it in Japan.

It was reading about one such four-day week success story that convinced Dean Tempest and his co-founders at London-based board games creator Big Potato Games to try it out with their own company. Big Potato has seen sales increase 350% since it started trialing a four-day working week in 2019, writing it into contracts the following year.

However, Tempest noted that employees understand that there is some flexibility needed for certain roles within the company. For instance, Big Potato's customer service team work on contract hours, rather than a four-day working week. Tempest said Big Potato needed to ensure its customers always have access to that team, "so that's just never going to work with a four-day week."

In addition, Tempest said that there's an "unwritten understanding" among all of Big Potato's staff that they may need to sometimes work on a Friday if there's a deadline, event or photo shoot, but added that the time off does tend to level out over the year.

And getting a third day off a week has unsurprisingly been a hit with Big Potato employees. Account manager Hannah Cornish said a four-day week has made a "massive difference" to have an extra day to do chores so she can enjoy the rest of her weekend.

Neither LUX, nor Big Potato Games cut employees' pay with the switch to a shorter working week.

Reducing carbon emissions and burnout

The environmental benefit of people commuting less is another argument for a four-day working week. A report published in May 2021, by the 4 Day Week campaign alongside the environmental and social justice collective Platform London, found that shifting to a four-day week by 2025 could slash the U.K.'s annual carbon footprint by 127 metric tons. That's the equivalent of 27 million cars off the road, which is the effectively the same as the U.K.'s entire fleet of private cars.

So, it seemed like a fitting model for sustainable events business Legacy Events. The Oxford-based company has operated on four-day week since 2018, in conjunction with a company rebrand. And with the event industry's issues with burnout, Legacy Events founder Abena Fairweather said she wanted to ensure a real work-life balance was embedded within her company's culture.

"You need to give people almost as much leisure time as they have at work," she said.

At the same time, Fairweather has struggled to get employees to take vacations.

"They don't feel they need to take two or three weeks away from work to go and recharge, but we all need longer times away from work," she said.

Her comments underline that a change in mindset may still be needed in the workplace, even among those employees who are able to enjoy this increased flexibility. But it seems as though, for the most part, the benefits have outweighed the costs for these companies.

Libby Hughes, an account director at Legacy Events, said a three-day weekend has given her more time to volunteer and visit friends and family.

"It's lovely to have that extra day to just go and visit my friends and family, but also wind down mentally, and I feel really refreshed by the Tuesday and ready to go," she said.

Legacy Events is also paying employees the equivalent of what they would earn in the sector if they were working a five-day week.

'Game changer'

So, could we see a four-day work week become the norm in the next five years?

Joe O'Connor, CEO of the 4 Day Week Global organization, said the pandemic has been a "game changer" for the movement.

In sectors such as technology, finance and some parts of professional services, O'Connor said that the momentum behind this working model was such that he could see it going from an ambition to the norm "really quickly, even in the space of two to three years."

O'Connor believed that competition would also propel change, not only on a corporate level, but in terms of government policy. He argued that there's a "reality driving home that as we emerge from the pandemic, taxation might not any longer be the big driver of competition between countries — it's quality of life."

"So, when it comes to attracting the best talent, attracting investment we could definitely see the four-day workweek becoming something that even countries turn to," he added.

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