Four-Day Work Week Statistics: What the Trials Show

A four-day week sounds simple: the same pay, one day less. For an employer it raises harder questions. Will the work still get done? Will customers notice? Does it help you keep people, or only feel good for a few months?

Most trials tested what their organizers call the four-day week: fewer working hours for the same pay. That differs from a compressed week, where people work the usual 40 hours in four longer days. This guide answers those questions from the trials themselves, with each figure's date, population and limits. It covers what the main trials measured and what happened to employees and to the business. It then flags the headline figures that need a second look, shows how employers have designed the week, and sets out how to run a trial of your own that produces a usable answer.

DisclosureJake Jorgovan co-founded Alpha Apex Group, which is mentioned in this article.

The main four-day week trials at a glance

The strongest evidence comes from coordinated trials that measured the same things before and after. The figures in the table are the studies' own.

What happened to employees

The clearest results are about people's well-being. In the UK pilot, before-and-after surveys found that 39% of employees were less stressed and 71% had lower levels of burnout by the end. Anxiety, fatigue and sleep problems fell, and 60% found it easier to combine paid work with care responsibilities. The report also found that 15% of employees said no amount of money would get them to accept a five-day schedule again.

In the UK, those gains held. The follow-up, published in February 2024, surveyed staff from 47 of the original organizations and found that the improvements in physical and mental health, work-life balance and burnout had been maintained a year on.

Wen Fan, Juliet Schor and colleagues published a six-country study with a comparison group in Nature Human Behaviour in July 2025. It analyzed 2,896 employees across 141 organizations in Australia, Canada, Ireland, New Zealand, the UK and the US. Burnout, job satisfaction, mental health and physical health all improved, "a pattern not observed in 12 control companies." Employees whose own hours fell most saw the largest gains, which were linked to better self-reported ability to do the job, fewer sleep problems and less fatigue.

Portugal's government-funded trial points the same way. Average weekly hours, including overtime, fell from 41.6 to 36.5, and the share of workers who struggled to balance work and personal life fell from 50% to 16%. Workers valued the four-day week at 28% of their salary on average, and 93% wanted to keep it.

There is a counterweight. In a June 2022 survey of 12,313 full-time employees, Gallup found (opens in a new tab) that the 8% who worked four days reported higher burnout than five-day workers, and no significant advantage in thriving. Gallup grouped people by how many days they typically work, so its four-day group can include compressed weeks of longer days; it did not evaluate a designed trial. The same research found that four-day workers had the lowest active disengagement, and that as many as 44% of on-site employees would change jobs for a four-day week. Its conclusion is worth keeping in view: the quality of the work experience had 2.5 to 3 times the effect on well-being of the number of days or hours worked.

What happened to the business

Most organizations that tried it kept it. In the UK, 56 of the 61 organizations continued immediately after the pilot, and a year later at least 54 still ran a four-day week, with at least 31 making it permanent. In Portugal, only four of 41 companies returned to a five-day week, and 80% of managers rated the trial as financially neutral. Only one Portuguese organization hired more workers to complete the trial.

On revenue, the UK report gives two measures. From the start to the end of the pilot, revenue rose 1.4% on average, weighted by company size, across the 23 organizations that supplied the data: broadly flat, which is what most employers would want to confirm. Compared with a similar earlier six-month period, 24 organizations reported a size-weighted average increase of 35%. The second figure is the one 4 Day Week Global's results page (opens in a new tab) leads with, as an "average increase in revenue", without the comparison it rests on.

Staff turnover and absence also fell. Resignations dropped from 2 to 0.8 per 100 employees, a 57% fall, and sick and personal days from 2.0 to 0.7 per employee per month. The report itself says these changes, and a fall in new hiring, could not be shown to be statistically significant, partly because of the small sample.

Iceland's public-sector trials cut hours from 40 to 35 or 36 a week. Productivity and service provision stayed the same or improved in most workplaces, and the trials were revenue neutral for the city council and the government. By June 2021, 86% of Iceland's working population had moved to shorter hours or gained the right to do so.

Single-company results are their own figures and do not separate the policy from everything else happening in the business. In its February 2023 release, Awin (opens in a new tab), a global affiliate platform, described moving its more than 1,300 staff to a flexible "Flexi-Week" after an 18-month trial. The release reports gross profit growth of 13% a year on average from 2019 to 2022, a window that starts before the trial, along with regrettable staff turnover down 33% and sick leave days down 21%.

Which four-day week statistics deserve a second look

Three more results need their limits attached.

Microsoft Japan's 40% productivity gain

The trial closed the offices every Friday in August 2019. Its October 2019 release listed sales per employee up 39.9% on August 2018. On November 8, 2019, Microsoft Japan added a notice: the figure was factual, but it was not achieved by the trial alone and came from various factors. The company moved it out of the trial's direct results. Those it kept were 25.4% fewer working days against August 2018, 58.7% fewer pages printed and 23.1% less electricity used (both against August 2016), and a 46% rise in the share of 30-minute meetings against August 2018.

Iceland's "four-day week"

Iceland tested a 35 or 36-hour week. It is good evidence on shorter hours, and weaker evidence on a fourth day off.

Who took part

The UK, Portugal and six-country cohorts were organizations that chose to try a four-day week. The UK pilot was organized by the 4 Day Week Campaign, 4 Day Week Global and the think tank Autonomy, groups that promote the idea, with academic researchers analyzing the data; of 70 companies that signed up, 9 did not begin. The UK sample leaned toward small firms: 66% had 25 or fewer employees, and the largest groups were marketing and advertising, professional services and charities. The results show what happened in organizations that wanted it to work. A 24-hour hospital or a factory line has less evidence behind it.

Hours did not always fall as far as a four-day week implies. In the UK pilot the average week went from 38 to 34 hours, not 32: a few companies cut less than eight hours, and in others people still did some work on their day off. The pilot also had no common productivity measure, so its business evidence rests on revenue, staffing and absence. Average work intensity rose slightly during the pilot, with 36% of employees saying it had increased and 31% saying it had fallen. The one-year follow-up survey, by contrast, found work intensity lower than before the pilot began.

Which countries have tried a four-day week?

The trials in this guide ran in the UK, Portugal and Iceland's public sector, and the six-country study added organizations in Australia, Canada, Ireland, New Zealand and the US. In Japan, Microsoft's local subsidiary ran its own one-month trial.

Four-day work week schedule examples

There is no single four-day week. The trials used several designs, and the differences matter for coverage and cost.

• The same pay for fewer hours. The UK pilot required pay to stay at 100% with a "meaningful" cut in working time. Organizations used a classic Friday off, staggered days so teams kept cover, decentralized arrangements set by department, annualized hours and conditional models.
• A nine-day fortnight. In Portugal, 51% of companies gave one day off every week and 49% one day off every two weeks.
• Four full days, or three full days plus two half days. Awin's February 2023 release described a choice of four full days, or three full days and two half days, on full salary.
• A whole-company day off. Microsoft Japan closed every office on Fridays for one month. Before choosing this design, decide how customers will be served while everyone is off.
• Fewer hours across the week. Iceland's trials cut the week from 40 to 35 or 36 hours, a reduction that need not mean a full day off.

A compressed week, described at the top of this guide, is different again: it changes when people work while keeping the hours the same.

One finding from the UK follow-up is worth applying to any design. Staff in organizations where the day off was only weakly guaranteed, or depended on hitting targets, had concerns about the policy, because they could not plan their time off.

What stops employers from trying it

Henley Business School surveyed 500 UK business leaders in November 2021. Among businesses that did not offer a four-day week, 75% named being available to customers as the biggest barrier (opens in a new tab), down from 82% in Henley's 2019 survey. Seventy percent thought it would be too complicated to manage, and 65% worried they would need more staff to cover, down from 80%. The share of employers who saw it as logistically problematic rose from 39% in 2019 to 47%.

Customer cover is hardest where work cannot wait: hospitals, emergency services, retail, hospitality, manufacturing lines and logistics. Iceland's trials did include shift workers at a police station and a hospital's internal medicine department, though they tested shorter hours rather than a shared day off. For these employers, a four-day week starts with shift scheduling, staffing costs and coverage before it means a day off.

How to run a four-day week trial that gives you an answer

None of these studies can tell you whether your organization will cope with a four-day week. A trial can. "When the path isn't clear, it's because you lack the facts to make the right decision," as I wrote in 2020. Six months of your own data will tell you more about your business than another survey percentage.

1. 1

   Measure a baseline first

   Collect six months of comparable data on the numbers you will judge the trial on: revenue or output per person, customer response times and satisfaction, resignations, absence, actual hours worked, including any work done on the planned day off, and overtime. Survey employees on burnout and workload before the trial, and repeat the same questions during it. The UK pilot collected six months of comparison data from each company, then monthly revenue, absence, resignations and new hires during the trial, plus up to two measures of the company's own.

2. 2

   Change how work is done before cutting the hours

   The UK organizations had two months of preparation. In Portugal, companies that made two or more organizational changes had an 8% chance of returning to five days, against 38% for those that made one or none. UK organizations that kept the policy revised their norms on meetings, communications and work prioritization, and Microsoft Japan's trial promoted 30-minute meetings and chat in place of some meetings.

3. 3

   Choose a design that protects customers

   Decide whether everyone takes the same day off or teams stagger it, and write down who covers each customer-facing hour. Guarantee the day off, so people can plan around it.

4. 4

   Decide in advance what "success" means

   Write the thresholds before the trial starts: for example, revenue and customer satisfaction no worse than the baseline, actual hours down, and absence, resignations and reported burnout lower.

5. 5

   Run it long enough to see past the novelty

   The coordinated trials ran for six months, and the UK follow-up found the well-being gains held a year later. At the end, judge the result against the thresholds you wrote down.

Image

Zoom

The approach described in this article, shown as a visual guide.

Is there a law for a 32-hour work week?

Federal law does not set a 32-hour threshold. Under the Fair Labor Standards Act, covered, nonexempt employees generally qualify for overtime after 40 hours (opens in a new tab) in a workweek. The proposed Thirty-Two Hour Workweek Act would lower that threshold. H.R. 10323 (opens in a new tab) was introduced on September 8, 2026 and referred to the House Committee on Education and Workforce. Representative Mark Takano, who reintroduced it with Senator Bernie Sanders (opens in a new tab), first introduced it in 2021.

As introduced, the bill would ultimately require overtime at one and a half times the regular rate above 32 hours a week for covered, nonexempt employees, along with daily overtime above eight hours and double time above 12 hours. Its text also includes transition provisions for newly covered employees. The daily rule matters for a compressed schedule of four ten-hour days. H.R. 10323 remained a proposal in October 2026.