Can switching to a 4-day workweek improve company productivity and employee mental health

I’ve been watching the 4-day workweek debate move from niche experiments to mainstream headlines for several years now. As someone who writes about the intersection of work, policy and wellbeing, I find the question deceptively simple on the surface — Can switching to a 4-day workweek improve company productivity and employee mental health? — but layered and context-dependent underneath. I’ll walk through the evidence I’ve seen, the common questions leaders and employees ask, and practical considerations for organisations thinking about trying it.

What do the experiments actually show?

There have been several high-profile pilots and studies — Microsoft Japan’s 2019 experiment, the Icelandic trials between 2015–2019, and the UK 4 Day Week trial (involving more than 60 companies) led by Autonomy and researchers at Cambridge, Oxford and Boston College. Companies like Perpetual Guardian in New Zealand and a number of smaller startups also reported benefits. The headlines often read the same: better wellbeing, sustained or improved productivity, and higher retention.

But the devil is in the details. “Improved productivity” doesn’t mean every task got done faster. It typically means outcomes — revenue per employee, customer satisfaction, or output — remained the same or improved while employees worked fewer hours. In many cases gains come from cutting wasted meetings, streamlining processes, and incentivising focused work. Mental health improvements are more straightforward: fewer hours, more recovery time, and reduced burnout risk translate into better reported wellbeing.

Why productivity can increase even with fewer hours

• Focus and intensity: When time is scarce, teams tend to prioritise and remove fluff. Meetings are shorter, email culture tightens, and people carve out longer uninterrupted blocks for deep work.
• Reduced presenteeism: Employees are less likely to “phone in” while exhausted. Instead of being at a desk for 40+ hours and performing poorly, they’re more engaged during a compressed week.
• Recruitment and retention effects: A four-day offer can attract better candidates and reduce turnover, saving hiring costs and preserving institutional knowledge.
• Wellbeing spillovers: Better mental health leads to fewer sick days, lower attrition, and often higher creativity — intangible but real benefits.

Common questions leaders ask (and my pragmatic answers)

Will our customers notice? Maybe — but probably not in a negative way if you design the shift thoughtfully. Customer-facing roles may need staggered schedules so someone from the company is always reachable. Alternatively, set clear expectations about response times. Transparency matters.

What about hourly-paid or essential services? A 4-day week with the same pay is easier to test in salaried knowledge roles. For shift-based, frontline, or hourly operations, you can experiment with compressed schedules, rotating days off, or pilot it in non-customer-facing teams first. Some retailers (and restaurants like Shake Shack in limited trials) have experimented with four-day schedules for managers, not necessarily all staff.

Does it just mean “work longer days”? That’s the concern I hear most. If you compress 40 hours into 32 by making days longer, you risk fatigue. Successful pilots typically reduce total hours (e.g., from 40 to 32) while encouraging greater efficiency — not longer days.

How do we measure success? Decide on metrics before you start. Common KPIs are output (sales, completed projects), quality measures (error rates, customer satisfaction), employee metrics (engagement surveys, sick days), and recruitment/retention data. Qualitative feedback is also crucial: regular check-ins and anonymous surveys capture nuances that numbers miss.

How to run a pilot — practical steps I’d recommend

• Start small: Pilot one team or function for 3–6 months. This limits risk and creates a learning lab.
• Define goals and metrics: Agree on what success looks like beforehand, and measure both productivity and wellbeing.
• Set ground rules: Clarify expected hours, availability, and communication norms. Are Fridays off for everyone, or do teams rotate?
• Train managers: Many failures come from weak implementation. Equip managers to run fewer, better meetings and to focus on outcomes.
• Enable focused work: Encourage meeting-free blocks, asynchronous communication, and tools that reduce context-switching (Slack channels, calendar rules, project boards).
• Collect feedback iteratively: Weekly pulse surveys and a formal end-of-pilot review are invaluable. Use both qualitative and quantitative data.

Realistic trade-offs and pitfalls

It’s not a magic bullet. Some organisations find productivity slips in certain functions, especially those requiring real-time collaboration across many teams or global timezones. Others discover hidden costs: scheduling complexity, the need for temporary hires to cover gaps, or cultural resistance from managers used to visibility over presenteeism.

There’s also a risk of “equity dilution.” If senior staff can choose their day off while junior staff can’t, resentment will build. Clear, fair policies and transparent decision-making are essential.

Evidence snapshot

How it impacts mental health — what the evidence and people say

Mental health improvements are the most consistent and least surprising outcome. People report less stress, more time for rest, family, exercise, or hobbies — and that matters. Burnout is not just an individual problem; it’s organisational. When companies reduce chronic time pressure, they reduce the conditions that produce anxiety, depression, and disengagement.

But mental health benefits are conditional. If a four-day week simply increases intensity without reducing expectations, stress can actually rise. That’s why the cultural change — valuing outcomes over hours — is as important as the calendar change.

Is this right for your company?

If you’re a leader, ask: can you measure output clearly? Are your customers flexible? Can managers be trained to lead by outcomes? If yes, a pilot makes sense. If your business depends on continuous physical presence (hospitals, emergency services), a wholesale shift might not be feasible, but aspects of the approach — protected focus time, fewer meetings, better leave policies — can still improve productivity and wellbeing.

I don’t think the 4-day workweek is a one-size-fits-all fix. But the experiments show it’s a powerful lever when implemented thoughtfully: it can sharpen priorities, protect mental health, and in many cases keep or even boost productivity. The important questions are less ideological — “Is it good?” — and more operational: “How will we do it, measure it, and ensure fairness?”