Experiments worldwide have tried to prove the benefit of working fewer hours, in the name of improving work-life balance. Can we get it down to a day a week?

If you’ve got a full-time job, chances are you’re working eight hours or more a day, probably Monday to Friday.

Of course, many of us work a lot more – Elon Musk said in a recent New York Times profile that he clocks up to 120 a week, pretty much obliterating any opportunity he has for work-life balance.

There aren’t many upsides to putting in so much time at the office: plenty of studies from around the world suggest longer working hours make us unhappier and less productive.

So in an effort to improve workers’ work-life balance, companies and governments around the world are experimenting with cutting working hours. It’s a move that attracts huge interest – a recent trial from New Zealand generated international headlines by cutting the work week from five days to four.

But why stop at four days? Why can’t we all work three, two, or even half a day each week? Is there a sweet spot where it doesn’t pay to work fewer hours?

Four-day experiment

Perpetual Guardian is the New Zealand-based trust and wills firm that experimented with removing an entire day from the working week.

Here’s how it worked: for two weeks in May, the company asked its 240 office workers to work four eight-hour days instead of five. (The workers were paid for five days.) Researchers from the University of Auckland and the Auckland University of Technology surveyed the employees afterwards. The result: 24% said their work-life balance had improved, and 7% saw reduced stress. Meanwhile, company leadership reported no drop in productivity.

Customer service even improved, says Jarrod Haar, a human resources and management professor at Auckland University of Technology who helped oversee the study. “When they rolled this out, the boss said if they can’t maintain 100% productivity, or thereabouts, in the four days, then back to normal it would go. So, staff have the motivation.”

This kind of experiment isn’t just taking place in the South Pacific, however.

In 2016, Reykjavik city government in Iceland revealed the results of a year-long study that cut around half a workday each week for full-time employees at some municipal offices. The experiment found that both costs and productivity remained the same, despite less time spent in the office.

Sweden did something similar, with a handful of trials involving a range of employers, from start-ups to nursing homes – most prominently at Svartedalen, an elderly care facility that launched a 32-hour work week.

In Japan, where there’s a word for “death by overworking,” the government has introduced a measure called “Shining Mondays” – in which companies can give employees the opportunity to come into work late one Monday a month.

 

Improving work-life balance saves companies money because happy employees are less likely to quit, says Jan Emmanuel De Neve, an associate professor of economics and strategy at the University of Oxford’s Saïd Business School. In his research, he has found work-life balance sits at the top of priorities for life satisfaction, even ahead of whether or not people find their jobs interesting.

“You want people to stay, because [employee] turnover is incredibly costly,” says De Neve, who is also an associate editor of the World Happiness Report. He also points out that in 1930, economist John Maynard Keynes predicted that we should all eventually be working just 15 hours a week, due to better technology and productivity gains.

Which raises the question…

How low can you go?

Just how short could we make the work week? What about four hours a week?

Author Tim Ferriss became famous almost 10 years ago with his book, The 4-Hour Workweek, that raised this idea. The theory being that you can escape a workaholic lifestyle by doing things like paring your regular work activities down to a twice-per-day email check, using online egg timers to speed your efficiency or outsourcing emails to virtual assistants.

It’s unlikely any company could still function with a workforce only showing up for a few hours a week – Ferriss’s book is more for individuals looking to maximise personal efficiency.

But cutting hours can make people more productive – in the Perpetual Guardian example, the shorter work week actually did change the way the team worked to get more done in a smaller amount of time. People arrived on time and didn’t leave early, for example, or skipped long breaks. (Quick reminder that we spend two hours every day on average on social media.)

If four-hour weeks are out, could we at least go down to a two- or three-day work week?

 

Not all it's cracked up to be

It’s not that easy, experts say – there is a tipping point where the costs start outweighing the benefits, even with a four-day work week.

The Swedish and New Zealand experiments mentioned above generated lots of headlines at the time – but we seldom hear about their aftermath. For example, Treehouse, a US online education company in Portland, Oregon, ended up reverting back to a “normal” 40-hour week after testing out a four-day scheme. Like many companies, Treehouse faced cutbacks and redundancies – and it was not a good look to have to lay off some workers while the rest continued to work four-day weeks.

Treehouse marketing director Megan Dorcey told BBC Capital that a standard five-day week, eight hours a day, also fostered better collaboration for the entire team (which is distributed across time zones in the US). Plus, customers wanted to be able to get service during standard business hours – another strike against a truncated work week.

As for the Swedish experiment at the Svartedalen care centre? It, too, didn’t last. (Mostly because it was designed to be temporary, but the results suggested such a scheme isn’t sustainable.) Henrik Dahlberg, press manager at the city of Gothenburg, says that it is back on the 40-hour work week.

Why? In order to let everyone work six hours a day, the care centre had to hire extra staff to keep up with the work — which cost more money. This scheme and others like it hit the local government’s budget, adding to the defecit within the welfare sector. “Considering that, it is hardly realistic to suggest drastic cuts in working hours,” Dahlberg says.

Dahlberg says that Left party leadership in the government has been pushing for more such trials, but the lack of trained staff and other economic conditions will make that unlikely. Dahlberg does point to a nearby Toyota plant that switched to a six-hour workday 13 years ago and is still on that schedule, however, as well as a department a university hospital that has done the same.

While cost is a large factor, there are other considerations, too.

Haar, of the New Zealand study, suspects diminishing returns would set in if you asked workers to show up less than four days a week – while slightly more workers would have job satisfaction working three days a week, the productivity hit just wouldn’t be worth it. “My gut says that the reduction of work time and maintaining efficiency might end at five days’ work into four,” Haar says.

Oxford professor De Neve agrees. Cutting more work days or hours “will become less and less and less impactful”, he says. By going from five to four days, “they’ve found that sweet spot already.”

As for long-term implementation at Perpetual Guardian? A spokesperson says the company has yet to make a decision on whether to make the four-day work week permanent – the board is still reviewing the results of the study and deliberating.

So, we can likely expect to see even more attempts to test out shorter work weeks in industries where it’s possible: more days off with fewer days to get it all done. We need to test Keynes’ hypothesis, after all.

“These options are more available and taken by more employees,” De Neve says. “This is far from a gimmick.”

Bryan Lufkin is BBC Capital’s features writer. Follow him on Twitter @bryan_lufkin

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