A new study published in Nature’s Humanities and Social Sciences Communications journal has confirmed what many workers have quietly hoped for: companies can switch to a four-day work week and not only survive, but thrive.
The research tracked 15 Australian companies that trialled the 100:80:100 model between 2022 and 2024.
The model is simple: workers receive 100% of their pay, work 80% of their previous hours, and commit to maintaining 100% of their previous output.
The results were striking.
14 of the 15 companies chose to continue with the four-day week after the trial ended.
Not a single one reported a drop in productivity.
Six companies saw productivity actually increase.
The rest said output stayed roughly the same.
These firms operated across a wide range of industries, from property management to publishing and health technology, which makes the findings harder to dismiss as a niche experiment.
How the Study Was Conducted
The research team, led by Professor John Hopkins of Deakin University, spent two years conducting in-depth interviews with companies that had formally adopted the 100:80:100 model.
Interviews took place between early 2023 and late 2024.
Each company was free to define productivity on its own terms.
Some measured revenue and profit.
Others tracked projects completed on time, staff turnover rates, absenteeism, or a metric called “net promoter score,” which gauges how likely customers are to recommend a business.
This flexibility was intentional.
Rather than imposing a single performance benchmark, the researchers allowed each company to measure what mattered most to them.
That design choice reflects something important: what success looks like differs by industry, and a rigid, one-size-fits-all measurement would have made the findings less applicable to the real world.
One company had already been running the four-day model for nearly eight years by the time researchers interviewed them.
One firm did abandon the trial, though the researchers noted that timing played a significant role in that decision, as the company was already going through a period of major internal change.
Findings From the Study
The headline finding is clear: not one company reported a productivity loss.
Six of the 15 companies said productivity had actually gone up since making the switch.
The remaining nine said it stayed about the same.
Those might sound like modest numbers, but consider what they mean in practice.
If you give your employees a full extra day off each week, maintain their salaries, and your output either stays the same or improves, the business case is difficult to argue against.
Burnout emerged as a major theme in the findings.
Six companies expressly said that reducing burnout, rather than boosting productivity, was their primary motivation for adopting the shorter week.
That distinction matters.
A 2025 survey by Beyond Blue found that one in two Australian workers currently experiences burnout, with young people and parents identified as the groups most at risk.
One CEO of a medium-sized health technology firm told researchers she judged the trial’s success by tracking levels of “attrition,” “absenteeism,” and “people taking sick days and mental health days because they’re burnt out.”
Another CEO at a financial services firm put it plainly: her company had been encouraging clients to live their best lives, and it felt wrong to hold employees to a different standard.
“As we grapple with high workplace burnout, and societal challenges about what to do with the productivity gains we’re predicted to get from AI, a four-day work week could be an interesting part of both those conversations,” said study lead Prof John Hopkins of Deakin University.
What Most People Get Wrong About This Model
Here is the part that tends to get lost in the conversation.
Most people hear “four-day work week” and imagine companies taking a leap of faith, crossing their fingers, and hoping productivity does not collapse.
The reality is quite different.
The 100:80:100 model is not simply about cutting a day.
It is about forcing companies and their employees to look honestly at how time is actually being spent.
Unnecessary meetings get cut.
Tasks that could be automated or delegated get reassigned.
Work that was never that valuable gets eliminated entirely.
The result is that employees are not cramming five days of work into four.
They are doing four days of genuinely focused, higher-quality work.
This is a crucial distinction, and it explains why concerns about productivity often prove unfounded.
The fear that workers will simply burn through five days of tasks in a compressed timeframe is rooted in a misunderstanding of how the model actually works.
Companies using this approach restructure their workflows before the shorter week begins.
Australia is not alone in seeing this play out.
In 2024, 45 German companies trialled the four-day model, and the majority were small or medium enterprises.
Financial performance during the trial showed no significant difference from the year before, which researchers interpreted as evidence of productivity gains since the same output was being delivered in fewer hours.
In the United Kingdom, more than 200 British companies have permanently adopted the four-day week without reducing pay, spanning industries from tech startups to charities.
How the Study Applies to Real Life
The practical question for most workers and managers is not whether the data is compelling.
It is whether the model is actually workable in their specific industry or role.
The Australian study provides some useful insight here.
Client-facing organisations handled the transition differently from non-client-facing ones.
Instead of all staff taking the same day off, many companies in client-heavy industries staggered days off across the team, ensuring clients always had someone available.
That flexibility is central to why the model held up across such different business types.
It is also why the conversation cannot be reduced to a simple yes or no.
A law firm and a software development studio will implement a four-day week very differently.
A call centre and a publishing house have completely different rhythms.
The research suggests that the most successful adoptions involve co-designed solutions where employees and leadership figure out together what restructuring actually looks like.
One of the more forward-looking threads in the research involves artificial intelligence.
As AI tools continue to automate repetitive tasks and boost individual output, the question of what workers do with those productivity gains becomes urgent.
The four-day week is one answer: let people reclaim some of that time rather than simply adding more tasks to the same workday.
Prof Hopkins specifically named this as a reason the conversation matters right now.
The assumption that technology always means doing more with the same number of hours is worth questioning.
The Criticism Worth Taking Seriously
The case for the four-day week is strong, but it is not without legitimate pushback.
Some researchers note that the benefits observed in short-term trials may not hold long-term.
There is a real possibility that the productivity gains seen in trials are partly driven by the novelty effect, where employees work harder because they are aware they are being observed or because the change feels exciting and new.
There is also the question of industries where a four-day model is structurally harder to implement.
Healthcare, emergency services, logistics, and hospitality do not run on fixed schedules in the same way a knowledge-work business does.
Any policy conversation about shortening the working week needs to reckon honestly with those sectors, not pretend they do not exist.
Scheduling complications are real, particularly for client-facing businesses and teams spread across different time zones.
The research also acknowledged that individual companies, not a research team, defined what productivity meant, which makes direct comparison between companies difficult.
None of this undoes the evidence.
But it does suggest the conversation needs to be more nuanced than simple celebration.
The Bigger Picture
What makes this Australian study particularly valuable is not just the findings.
It is what the findings reveal about the assumptions underneath how most of us work.
The five-day, 40-hour week was not handed down as a law of nature.
It was a labour movement achievement, standardised in the 20th century as industrialisation scaled up.
The conditions of work have changed dramatically since then.
Knowledge work, remote collaboration, and AI-assisted tasks have transformed what a productive hour actually looks like.
The 15 Australian companies in this study effectively ran a live experiment on that assumption, and the data came back in favour of change.
Not one of them reported falling behind.
Most of them either held steady or improved.
And 14 of 15 chose not to go back.
That is not a fluke.
That is a signal worth paying attention to, whether you are a manager wondering if your team could handle it, an employee hoping your company will consider it, or a policymaker thinking about what the future of work should actually look like.
The conversation is no longer theoretical.
It is already happening.
The only question left is who joins it next.
References and Further Reading
