Does the four-day workweek actually boost productivity and well-being?
Yes — and the evidence is surprisingly consistent across different countries and industries. The strongest quantitative finding comes from a study of technology companies in Brazil, where one firm saw a 120% increase in revenues within just five months of adopting a four-day week [4]. That's not a typo: revenues more than doubled. The same study reported a lighter work environment and lower stress levels, suggesting that the productivity gain wasn't achieved by burning people out [4].
A larger, more rigorous study of 604 employees in Indian service and manufacturing companies found that the four-day workweek significantly improved performance, but only when certain conditions were met: strategic planning at work, viewing the company as a brand, continually connecting with colleagues, and inspiring happiness at work [3]. Psychological well-being acted as a moderator, meaning that employees who were already in a good mental state benefited even more [3]. This tells us the model amplifies existing strengths rather than fixing broken cultures.
Interviews with 15 Australian firms that trialled the '100:80:100' model (100% pay, 80% hours, 100% productivity) revealed that a 25% increase in hourly productivity was not required to maintain previous performance levels — in other words, companies didn't need a miracle to break even [1]. The same study found that boundaries between work and non-work were clearly communicated, and 'boundary permeability' (work leaking into personal time) was low, which directly supports the well-being claims [1].
What are the real risks and limitations?
The evidence also reveals clear pitfalls. A UK-based study that interviewed 14 employees across education, finance, healthcare, and manufacturing found that while employees saw the four-day week as an opportunity for better work-life balance, they raised serious concerns about increased workload pressure, coordination difficulties, and financial viability — especially in roles requiring continuous operations like healthcare or manufacturing [2]. This study is valuable because it captures the perspective of employees who have NOT yet made the switch, giving a realistic picture of the fears and barriers [2].
The Australian study of 15 firms confirmed that successful adoption requires 'clear motivations for change, adequate planning and training, and established measures for evaluating both short-term and long-term success' [1]. Without those elements, the model can backfire. The same study noted that academic studies into the 100:80:100 model are 'currently lacking', meaning the evidence base is still thin — most of what we have comes from early adopters who were already motivated to make it work [1].
A case study of a digital marketing agency that adopted the four-day week found that even with a time-management tool (the Pomodoro technique), the model could lead to 'personalising productivity' — meaning employees felt pressure to manage their own time more intensely, which could increase stress if not handled well [5]. However, the same study found that under the right conditions, the tool also fostered cooperation and better work-life balance, showing that the outcome depends heavily on implementation [5].
What conditions make a four-day workweek succeed?
The evidence points to three key ingredients: leadership commitment, clear performance metrics, and role suitability. The Australian study emphasised that the model works best when it is 'management-led and employee-driven' — top-down support combined with bottom-up buy-in [1]. The Indian study added that 'strategic planning at work' and 'inspiring happiness at work' were among the most important factors for boosting performance [3].
Role suitability matters a lot. The UK study highlighted that continuous-operations roles (like healthcare or manufacturing) face coordination difficulties that office-based or project-driven roles do not [2]. The Brazilian study focused on technology companies, which are naturally suited to flexible, output-based work [4]. So the model is not one-size-fits-all: it works best where work can be measured by outcomes rather than hours.
Finally, the evidence suggests that the four-day week can support broader goals like the UN Sustainable Development Goals — specifically SDG3 (good health and well-being), SDG5 (gender equality), and SDG8 (decent work and economic growth) [1]. This is a reminder that the model is not just about productivity; it's also about creating healthier, more equitable workplaces.
About These Sources
This answer is built on 5 peer-reviewed studies — published from 2022 to 2026, 3 from 2024 or later, 1 in Q1 journals — selected as the most relevant from 5 studies that passed quality screening, drawn from 54 papers retrieved from a database of over 500 million.
Sources used in this answer
The four-day workweek in Australia: insights from early adopters of the 100:80:100 model
Interviews with 15 Australian firms that trialled the 100:80:100 model found that a 25% increase in hourly productivity was not needed to maintain performance, and that clear boundaries between work and non-work were key to success.
From Five to Four: Examining Employee Perspectives Towards the Four-Day Workweek
A UK study of 14 employees across diverse sectors found that while employees saw the four-day week as an opportunity for better work-life balance, they raised concerns about workload pressure, coordination difficulties, and financial viability in continuous-operations roles.
The Subtle Art of Effecting a Four-day Workweek to Drive Performance
A survey of 604 employees in Indian service and manufacturing companies found that strategic planning, viewing the company as a brand, continual connection, and inspiring happiness at work significantly improved performance under a four-day week, with psychological well-being acting as a moderator.
The influence of the four-day work week on technology companies in Brazil
A study of technology companies in Brazil reported that firms adopting a four-day week saw increased productivity, a lighter work environment, and in one case a 120% increase in revenues within five months.
Time management between the personalisation and collectivisation of productivity: The case of adopting the Pomodoro time-management tool in a four-day workweek company
A case study of a digital marketing agency found that the Pomodoro time-management tool, when used in a four-day week context, could lead to both personalising productivity and instances of collective working towards better work-life balance, depending on implementation.