With the rise of popular work chat apps like Slack and easy access to corporate email 24/7 through our smartphones, breaking away from work can feel more difficult than ever.

At the same time, employee burnout appears to be on the rise. In a study of 75,000 employees published last year in June, Gallup found that 23% of workers reported feeling burned out always or very often at work, while another 44% reported feeling burned out sometimes. A study of 614 human resources leaders conducted by Kronos Incorporated and Future Workplace in 2017 also found that nearly half of those surveyed said burnout is the cause of up to half of their yearly workforce turnover.

Now, it seems a growing number of companies are hoping to combat that trend by finding ways to improve work-life balance — most notably by experimenting with a four-day workweek. While the four-day workweek is still far from common, it certainly seems to be growing in popularity.

Fifteen percent of the 60,000 US companies that participated in the Society For Human Resource Management's survey conducted in April 2019 said they offer a four-day workweek of 32 hours or less. That's up from 13% in 2017 and 12% in 2018. What's more, the organizations that have implemented this shorter workweek didn't report a decrease in productivity or revenue, the study says.

Microsoft made headlines recently when it published the results of a trial it held at a subsidiary in Japan, during which it closed its offices every Friday during the month of August. The company found that doing so led to a 40% boost in productivity.

Here's a look at other major companies that have tried switching to a four-day workweek, from Shake Shack to Uniqlo.

Shake Shack is one of several companies experimenting with a four-day workweek

Image: Instagram / Shake Shack

The popular burger chain began experimenting with a four-day workweek at some Las Vegas-based locations back in March, and now about one-third of the company's locations have adopted the policy.

Although the four-day work schedule is still in a test phase, the results seem promising so far, CEO Randy Garutti said on the company's most recent earnings call.

"We're really listening to our managers, understanding what their lifestyles are like, what are the things they want," he said. "We're hearing things like, 'Wow, this is so powerful.'"

The four-day workweek has prevented some employees from having to pay for childcare for a fifth day, and for others it's part of what motivated them to apply for the job, said Garutti.

Basecamp allows employees to work four days per week during the summer

Image: Basecamp

During the summer months, the staff at project management software company Basecamp gets to work four days per week, resulting in a 32-hour workweek. The policy is in effect from May 1 through August 31, although new employees may be required to complete a training period.

The 32-hour workweek helps employees focus on the tasks that are most important to their job, Chase Clemons, Basecamp's customer support team lead, said in an interview with CNBC.

"Thirty-two hours forces us to prioritize what we work on," Clemons said to the outlet. "It's not about working faster, but rather working smarter."

Uniqlo ran a trial in 2015 that allowed employees to work 40 hours over the course of four days instead of five

Image: Reuters

Uniqlo parent company Fast Retailing announced in 2015 that the Japanese clothing company would allow one-fifth of its employees to take a four-day workweek. Workers still have to put in 40 hours per week, however.

Fast Retailing offered the perk to full-time store workers with the goal of preventing employees from switching to part-time to achieve a better work-life balance, Bloomberg reported when the policy was introduced.

Perpetual Guardian adopted the four-day workweek on a long-term basis after a successful trial.

Andrew Barnes, founder of New Zealand-based estate planning service provider Perpetual Guardian, may be the biggest supporter of the four-day work week yet.

His company ran a trial in March 2018 that involved giving all 240 of its staff across New Zealand one paid day off per week. Employees worked 30 hour weeks but were paid the same and were required to produce the same amount of work.

After the trial, the company found that team engagement had increased noticeably, while work-life balance and stress decreased. The company has been implementing the policy on a long-term opt-in basis since last November.

Barnes has been a vocal advocate of the four-day workweek ever since, and even established a nonprofit organization to support the idea.

Treehouse CEO Ryan Carson found that the four-day workweek didn't pan out as planned

Not all trial runs of the four-day workweek have proven successful.

Treehouse, a company that offers virtual classes for learning how to code, tried the four-day workweek in 2015. But it nixed the policy in 2016, company CEO Ryan Carson said when speaking during GrowthLab Live in 2018.

"It created this lack of worth ethic in me that was fundamentally detrimental to the business and to our mission," Carson said last year. "It actually was a terrible thing."

Wildbit implemented a four-day workweek in 2017 and has been iterating on the approach since

Software company Wildbit also ran a trial in 2017 that involved taking Fridays off.

"We're challenging ourselves that by limiting our time, we'll produce more thoughtful and important work than when we had 40 hours to get it all done," cofounder and CEO Natalie Nagele wrote in 2017.

Since then, the company has experimented with the format to adjust for busier periods of the year. It eventually moved to giving some support team members Mondays off instead of Fridays, and has considered implementing shorter workdays instead of full days off, according to Fast Company.

Nagele also told the outlet that the company launched more features in its first year of implementing the four-day workweek compared to the previous year. The system also helped employees avoid distractions and focus on priority tasks.