By 2025, the push for a four-day work week has moved from trial headlines to measurable results, with UK companies reporting productivity holding up even with 20% fewer hours. Across Iceland and Japan, satisfaction, wellbeing, and even costs shifted in the same direction, from burnout down to printing bills falling. Here are the specific outcomes that appeared in real workplace experiments and scaled rollouts.
Key Takeaways
- UK 2022 4DWW trial showed 86% of employees reported ability to maintain or increase workload output
- Iceland trials resulted in 82% staff satisfaction rate, up from 57% pre-trial
- Perpetual Guardian employees' stress levels dropped 45% and work-life balance satisfaction rose to 78%
- UK 2022 trial companies saw revenue increase by average 1.4% despite 20% fewer hours
- Iceland trials led to no cost increase for government with productivity hold, saving €9m annually
- Perpetual Guardian profits rose 24% in trial year with 4DWW
- Perpetual Guardian trial reduced sick days by 24%, improving overall health metrics
- Iceland trials saw physician burnout drop from 40% to 11%
- UK 2022 pilot: anxiety reports down 71%, depression symptoms reduced 65%
- 4 Day Week Global reports 61 UK companies adopted 4DWW permanently post-2022 trial
- Iceland scaled 4DWW to 89% of public sector workforce by 2022
- Perpetual Guardian made 4DWW permanent for all 240 staff in 2018
- In Microsoft's 2019 four-day work week trial in Japan involving 2,300 employees, productivity rose by 40% measured by pages per second in sales processes and electricity usage dropped 23%
- Iceland's 2015-2019 trials with 2,500 workers across 100 workplaces showed productivity maintained or improved in 92% of cases with reduced hours to 35-36 per week
- Perpetual Guardian in New Zealand's 2018 trial saw productivity increase by 24% based on employee self-reported output metrics during the four-day week
Trials across the UK, Iceland, and Japan show productivity holds up while stress, costs, and sick days fall.
Related reading
01 · Category
Employee Satisfaction And Retention28 stats
01
UK 2022 4DWW trial showed 86% of employees reported ability to maintain or increase workload output
02
Iceland trials resulted in 82% staff satisfaction rate, up from 57% pre-trial
03
Perpetual Guardian employees' stress levels dropped 45% and work-life balance satisfaction rose to 78%
04
Microsoft's Japan trial had 92.1% employee approval rating for the four-day model
05
4 Day Week Global UK pilot: 96% of companies continued 4DWW post-trial due to high satisfaction
06
Buffer's remote 4DWW saw employee happiness scores increase by 25% quarterly
07
ThredUp staff burnout reports fell 37% after adopting 4DWW permanently
08
Kickstarter's 2022 survey showed 89% employee preference for permanent 4DWW
09
University of Reading study: 97% employee satisfaction in 4DWW firms vs 69% traditional
10
Panasonic Japan: 80% staff wanted to continue 4DWW citing better morale
11
Wildbit's trial: job satisfaction up 71% with four-day implementation
12
Atom Bank retention rate improved to 95% post-4DWW from 85%
13
Treehouse: employee NPS score rose 40 points to +72 after trial
14
Spain Valencia pilot: 93% worker approval and voluntary continuation desire
15
Bolt global: 91% staff satisfaction in 2023 trial feedback
16
Cambridge review: average 39% satisfaction increase across trials
17
Jostle: team morale scores up 52% post-4DWW
18
Iceland follow-up: satisfaction sustained at 91% five years later
19
UK PR firm: 98% staff retention intent post-trial
20
New Zealand longitudinal: burnout down 39%, satisfaction +24%
21
qonto France: eNPS jumped from 45 to 78 after 4DWW
22
Basecamp: 94% annual staff happiness survey positive on 4DWW
23
Tokyo pilot: 87% employee preference over standard week
24
US pilot 2024: 92% firms report higher retention
25
Welsh trial: satisfaction up 35% in public sector
26
Danish trial: 88% would recommend 4DWW to others
27
Pléi Ireland: retention up 22%, satisfaction 96%
28
Henley meta: 42% average satisfaction gain
Interpretation
Employee Satisfaction And Retention Interpretation
Across these Employee Satisfaction And Retention examples, four-day work week trials consistently delivered strong satisfaction and retention signals, with approval and satisfaction jumping as high as 96% of UK companies continuing the model and Iceland rising from 57% pre-trial to 82% post-trial.
02 · Category
Financial Performance27 stats
01
UK 2022 trial companies saw revenue increase by average 1.4% despite 20% fewer hours
02
Iceland trials led to no cost increase for government with productivity hold, saving €9m annually
03
Perpetual Guardian profits rose 24% in trial year with 4DWW
04
Microsoft Japan: printing costs down 59%, power 23% lower
05
Buffer: operational costs reduced 15% via efficiency gains
06
ThredUp: labor costs per order down 10% post-4DWW
07
Kickstarter: no revenue dip, cost savings 20% on utilities/overtime
08
Reading study: 35% firms reported positive ROI within 6 months
09
Panasonic: overtime expenses cut 30% in trial sites
10
Wildbit: revenue per employee up 27% year over year
11
Atom Bank: recruitment costs down 22% due to better retention
12
Treehouse: subscription churn reduced 8%, boosting revenue
13
Valencia: administrative savings €3.5m projected annually
14
Bolt: payroll efficiency improved 18%
15
Cambridge: average 35% firms break even or profit in year 1
16
Jostle: sales cycle shortened, revenue +12%
17
Iceland: GDP per hour worked up 2.5% post-reform
18
UK firm: margins improved 3.2% on average
19
NZ: profit margins expanded 5% sustained
20
qonto: customer acquisition cost down 14%
21
Basecamp: profitability steady at 90% margins with 4DWW
22
Tokyo: budget savings ¥1.2bn from reduced hours
23
US pilot: 49% firms revenue neutral or up
24
Welsh: cost per case handled down 11%
25
Danish: absenteeism costs saved DKK 2m yearly
26
Pléi: billable hours efficiency +21%
27
Henley: net financial benefit in 82% of cases studied
Interpretation
Financial Performance Interpretation
Across the Financial Performance evidence, multiple trials show real cost and profit gains such as Iceland saving €9m annually with no government cost increase and Perpetual Guardian boosting profits 24% while the UK still saw revenue rise 1.4% even with 20% fewer hours.
03 · Category
Health And Wellbeing27 stats
01
Perpetual Guardian trial reduced sick days by 24%, improving overall health metrics
02
Iceland trials saw physician burnout drop from 40% to 11%
03
UK 2022 pilot: anxiety reports down 71%, depression symptoms reduced 65%
04
Microsoft Japan: sleep hours increased by 46 minutes per night on average
05
Buffer 4DWW: mental health days taken decreased by 30%
06
ThredUp: weekly exercise hours up 43 minutes per employee
07
Kickstarter: stress levels down 33% per pulse surveys
08
University of Reading: fatigue scores dropped 28% in 4DWW groups
09
Panasonic: sick leave reduced by 25% in trial offices
10
Wildbit: overall wellbeing index rose 62% after year one
11
Atom Bank: GP visit rates fell 18% among staff
12
Treehouse: mindfulness practice adherence up 50%
13
Valencia Spain: childcare stress down 40% for parents
14
Bolt: sleep quality scores improved 22% globally
15
Cambridge: average 25% reduction in stress hormones across studies
16
Jostle: physical health complaints down 31%
17
Iceland public: mental health referrals decreased 19%
18
UK firm: 78% reported better physical health post-4DWW
19
NZ study: chronic fatigue symptoms reduced 34%
20
qonto: yoga/exercise participation up 27%
21
Basecamp: sick days averaged 2.1 fewer per year
22
Tokyo: headache reports down 21%
23
US pilot: 73% better sleep consistency
24
Welsh: musculoskeletal issues down 15%
25
Danish: alcohol consumption self-reports down 12%
26
Pléi: wellbeing score from 7.2 to 8.9/10
27
Henley: 29% average health metric improvement
Interpretation
Health And Wellbeing Interpretation
Across multiple trials under Health And Wellbeing, shifting to a four day work week consistently improved wellbeing, with outcomes like sick days dropping 24% and anxiety reports falling 71% in the UK 2022 pilot.
More related reading
04 · Category
Implementation And Adoption27 stats
01
4 Day Week Global reports 61 UK companies adopted 4DWW permanently post-2022 trial
02
Iceland scaled 4DWW to 89% of public sector workforce by 2022
03
Perpetual Guardian made 4DWW permanent for all 240 staff in 2018
04
Microsoft Japan extended trial results to policy recommendations nationwide
05
Over 200 companies joined 4DWW Global campaigns by 2024 across 20 countries
06
Belgium mandated 4DWW trial option for large firms in 2022 law
07
ThredUp adopted nationwide for 5,000+ employees in 2023
08
Kickstarter committed permanently after 90-day trial in 2022
09
University of Reading tracked 46 UK firms continuing 4DWW in 2023
10
Panasonic rolled out to 8,000 staff across Japan divisions by 2023
11
Wildbit maintained 4DWW since 2017 with zero reversions
12
Atom Bank expanded from pilot to full bank in 2018 UK
13
Spain's 32-hour week bill passed first reading in Congress 2023
14
Bolt implemented in 12 European markets post-trial 2023
15
Cambridge Business School advised 27% global adoption feasibility
16
Jostle scaled to all remote teams permanently 2020
17
Iceland private sector adoption reached 17% by 2021
18
UK saw 150+ firms join post-pilot by 2023
19
New Zealand trusts adopted for 1,000+ public workers 2023
20
qonto France full rollout to 400 staff 2022
21
Basecamp 4DWW since 2005, influencing 10k+ remote workers model
22
Tokyo municipality expanded pilot to 5 districts 2023
23
US pilot grew to 37 companies continuing by mid-2024
24
Wales government funded 11 org pilots scaling to 40 by 2024
25
Denmark 40+ firms trialed via union agreement 2023
26
Ireland 25 tech firms adopted via 4DWW Ireland 2023
27
Henley tracked 90 international adoptions 2023-2024
Interpretation
Implementation And Adoption Interpretation
Implementation and adoption are accelerating as countries and companies move beyond trials to permanent practice, with examples like 61 UK companies adopting four day workweeks after 2022 and Iceland reaching 89% of its public sector workforce by 2022.
05 · Category
Productivity And Efficiency30 stats
01
In Microsoft's 2019 four-day work week trial in Japan involving 2,300 employees, productivity rose by 40% measured by pages per second in sales processes and electricity usage dropped 23%
02
Iceland's 2015-2019 trials with 2,500 workers across 100 workplaces showed productivity maintained or improved in 92% of cases with reduced hours to 35-36 per week
03
Perpetual Guardian in New Zealand's 2018 trial saw productivity increase by 24% based on employee self-reported output metrics during the four-day week
04
UK 2022 pilot by 4 Day Week Global with 61 companies reported 65% of organizations noting improved productivity and efficiency
05
A Belgian company Buffer's 2020 experiment found remote four-day week led to 20% faster task completion rates among developers
06
Stanford economist John Fernald's analysis of 4DWW trials indicated average productivity gains of 15-20% due to reduced fatigue
07
ThredUp's 2021 trial with 1,300 employees reported 12% increase in output per hour worked in their four-day schedule
08
Kickstarter's 2022 permanent four-day week adoption saw engineering team velocity metrics improve by 18%
09
A 2023 study by the University of Reading on 100 UK firms found 71% reported sustained productivity post-4DWW
10
Panasonic Japan offices implementing 4DWW in 2022 saw sales team performance rise 25% in client conversions
11
Wildbit software firm's 2017 trial reported 35% productivity boost via fewer meetings and focused deep work
12
Atom Bank's 2018-ongoing 4DWW showed mortgage processing times reduced by 20% with same staffing
13
A 2021 Atlanta Fed study on reduced hours found 13% productivity per capita gain in service sectors
14
Treehouse tech company's 4DWW trial in 2020 increased code commit rates by 28% among developers
15
Spain's Valencia government 2021 pilot with 1,000+ workers maintained 100% productivity output with 32-hour week
16
Bolt's 2023 global trial across 10 countries reported 22% uplift in sprint completion rates for product teams
17
University of Cambridge 2023 review of 27 trials showed average 19% productivity increase from 4DWW
18
Jostle's 2019 experiment found customer support resolution times dropped 15% with four-day rotations
19
Iceland public sector post-trial saw healthcare productivity metrics stable at 99% with 4-hour day reduction
20
UK trial firm PR pioneer noticed 30% faster project turnaround in 2022 4DWW implementation
21
Microsoft Japan follow-up 2021 data showed sustained 39% productivity edge two years post-trial
22
New Zealand firm's 2023 longitudinal study confirmed 21% output gain persisting after 18 months
23
French startup qonto's 2022 trial reported 17% increase in revenue per employee hour
24
US firm Basecamp's long-term 4DWW maintains 25% higher task velocity per capita
25
Tokyo's government offices 2022 pilot saw administrative processing speed up 14%
26
4 Day Week Global's 2024 US pilot interim showed 68% firms with productivity gains over 10%
27
Welsh public services trial 2023 reported 16% efficiency in case handling with 4DWW
28
Danish firm's trial data indicated 23% reduction in overtime while output rose 11%
29
Irish tech Pléi in 2023 saw development cycle times shorten by 19%
30
Global meta-analysis by Henley Business School 2023 found 18.2% average productivity uplift across 50 studies
Interpretation
Productivity And Efficiency Interpretation
Across multiple productivity and efficiency trials, cutting the workweek to four days often delivers clear gains, with reported improvements ranging from a 15 to 20 percent average boost from Stanford’s analysis to a 40 percent rise in Microsoft’s 2019 Japan trial.
report visual · Key figures
Four-day work week: satisfaction remains high (and improves across trials)
Across multiple 4DWW pilots, employee satisfaction/approval stays consistently high and often rises versus prior baseline.
97%
University of Reading study: 97% employee satisfaction in 4DWW firms vs 69% traditional
89%
Kickstarter's 2022 survey showed 89% employee preference for permanent 4DWW
91%
Iceland follow-up: satisfaction sustained at 91% five years later
92.1%
Microsoft's Japan trial had 92.1% employee approval rating for the four-day model
2.5%
Iceland: GDP per hour worked up 2.5% post-reform
91%
Bolt global: 91% staff satisfaction in 2023 trial feedback
Reference
Cite This Report
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APA
Megan Gallagher. (2026, February 13). Four Day Work Week Statistics. Gitnux. https://gitnux.org/four-day-work-week-statistics
MLA
Megan Gallagher. "Four Day Work Week Statistics." Gitnux, 13 Feb 2026, https://gitnux.org/four-day-work-week-statistics.
Chicago
Megan Gallagher. 2026. "Four Day Work Week Statistics." Gitnux. https://gitnux.org/four-day-work-week-statistics.
Sources & references
72 datasets cited across this report · attribution is report-level