The four-day workweek is picking up steam across the globe. 

Dozens of countries including Ireland, Spain and the UK have tested a 4-day workweek, with overwhelmingly positive results: Businesses that participated in a six-month trial in the UK, which ended in December 2022, said switching to a 4-day workweek improved productivity, morale and team culture.

On the employee side, people said having more personal time reduced burnout and boosted life satisfaction, according to self-reporting from trial participants.

Although no country has fully adopted a 4-day workweek, some countries are experimenting with one or have policies that allow workers to request a shorter schedule. Here are four countries where the 4-day workweek has been widely adopted, or is being tested:

South Africa

More than 500 employees at 28 companies are participating in South Africa's 4-day workweek trial, which began in March and will continue until September. A second trial is planned to start in June. 

The experiment is being run by 4 Day Week South Africa, which is a branch of 4 Day Week Global, the same group that helped organize the UK trial. 

There are 28 companies and more than 500 employees participating in the trial, says Karen Lowe, director of 4 Day Week South Africa. 

The experiment uses a 100-80-100 model: workers receive 100% of the pay for working 80% of the time and still delivering 100% of their usual output. 

Belgium

In early 2022, the Belgian government announced a reform package that gives workers the right to work four days instead of five without losing their salary. The law officially went into effect in November 2022.

Under this scheme, workers are still expected to maintain the same amount of hours over four (longer) days instead of five and would have an extra day off to compensate. 

Employers, however, still have the right to turn down an employee's request for a shortened workweek, on condition that they submit their refusal in writing and give solid reasons for their decision.

"The goal is to give people and companies more freedom to arrange their work time," Belgium Prime Minister Alexander de Croo said in February 2022, as reported by Bloomberg. "If you compare our country with others, you'll often see we're far less dynamic."

Iceland

Between 2015 and 2019, Iceland led one of the largest 4-day workweek pilots to date, with close to 2,500 people participating. 

The trial was considered an "overwhelming success" among researchers, with employees reporting improved well-being, work-life balance and productivity.

As of 2022, workers represented by unions in Iceland — close to 90% of the workforce — have won the right to request a shorter workweek, says Alex Soojung-Kim Pang, the global programs and research manager for 4 Day Week Global.

However, uptake of the 4-day workweek among businesses in Iceland's private sector "seems to be slow," he adds, as many employers are placing the onus on individuals to negotiate for worktime reductions instead of offering a 4-day workweek as an automatic benefit to all employees.

Japan

In 2021, the Japanese government's annual economic policy guidelines included a recommendation that companies let employees opt for a four-day workweek and, by extension, a 3-day weekend. Kuniko Inoguchi, a Japanese politician from the Liberal Democratic Party and economist, spearheaded the proposal.

The recommendation to switch to a 4-day workweek is meant to improve employees' work-life balance, giving them more time to take care of family members, further their education or go out with friends, the Washington Post reports. 

There are a number of companies in Japan that have experimented with 4-day workweeks, including Microsoft and Panasonic, which piloted 4-day workweeks for their Japan-based employees in 2019 and 2022, respectively. 

Other companies in Japan have implemented the 4-day workweek permanently, says Pang, including banking giant Mizuho and tech firm Cross River, whose CEO, Shinji Koshikawa, has been a "vocal advocate" for a 4-day workweek.

For decades, the 4-day workweek was seen as a fringe concept that wouldn't catch on — but now, it's become a serious policy consideration for businesses struggling to combat burnout and retain employees. 

The share of companies offering a 4-day workweek benefit reached the 10% threshold for the first time last year, according to a recent Payscale report. 

"Employees are looking for flexibility," Payscale pay equity analyst Ruth Thomas recently told CNBC Make It, "potentially as they continue to experience a decline in real wage growth [and] seeing themselves working longer hours, they're seeking some level of return."

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