4-Day Workweek Pilot Results: Analyzing the Data from US and UK Trials

The concept of a four-day workweek has moved from a theoretical perk to a data-backed business strategy. Recent large-scale trials conducted in the United Kingdom and the United States have provided concrete evidence regarding productivity, revenue, and employee health. For business leaders and HR professionals, these results offer a compelling look at how reducing hours without cutting pay can stabilize turnover and maintain output.

Understanding the "100-80-100" Model

To understand the results of these pilots, you must first understand the methodology used. The trials, organized by the non-profit advocacy group 4 Day Week Global in partnership with researchers from Boston College and the University of Cambridge, utilized the “100-80-100” model.

This model is strictly defined as:

  • 100% of the pay: Employees do not take a pay cut.
  • 80% of the time: Working hours are reduced, typically from 40 to 32 hours.
  • 100% of the productivity: The expectation is that output remains the same despite fewer hours.

This distinguishes the pilot from a compressed workweek, where employees work four 10-hour days. In these recent trials, the goal was genuine hours reduction.

The UK Trial: The World's Largest Pilot

From June to December 2022, the United Kingdom hosted the largest trial of this nature to date. It involved 61 companies and approximately 2,900 workers. The industries ranged from office-based marketing agencies to physical businesses like a fish and chip shop in Norfolk.

Revenue and Productivity Findings

The primary concern for most executives is the bottom line. The data from the UK report dispels the myth that fewer hours equal less money.

  • Revenue Stability: Across the participating companies, revenue remained broadly the same during the six-month trial period.
  • Revenue Growth: When compared to a similar period from previous years, average revenue actually rose by 35%.
  • Adoption Rates: The most telling statistic of success is continuation. Of the 61 companies that entered the pilot, 56 decided to continue with the four-day week immediately after the trial ended. Eighteen of those companies made the change permanent instantly.

Staff Turnover and Absenteeism

While revenue remained stable, the costs associated with staffing dropped significantly.

  • Retention: The number of staff leaving participating companies dropped by 57% during the trial period.
  • Sick Days: Employee sick days decreased by 65%.

For businesses like Tyler Grange, an environmental consultancy that participated, this reduction in absenteeism translated directly to preserved margin and reduced administrative burden.

The US and Ireland Trial Results

A separate but coordinated pilot program ran nearly simultaneously in the United States and Ireland. This cohort included 33 companies and just over 900 employees. The results mirrored the UK findings, suggesting that the success of the model is not culturally specific to Britain.

Performance Metrics

The US participants reported a weighted average revenue increase of 8% during the trial itself. When compared to the same period in the previous year, revenue was up 38%.

Employees in this cohort were asked to rate their experience on a scale of 0 to 10. The average rating was 9.1. Perhaps most significantly, 97% of employees stated they wanted to continue the four-day schedule.

When asked what it would take to return to a five-day schedule, 42% of employees said they would require a salary increase of 25% to 50%. Thirteen percent stated that no amount of money could convince them to go back to five days.

Specific Brand Examples and Outcomes

General statistics are useful, but looking at specific companies helps visualize how this works in practice.

Kickstarter

The crowdfunding platform Kickstarter was one of the premier names involved in the US pilot. Their internal data showed that project launch rates and funding success metrics remained steady, proving that high-pressure tech environments could sustain the schedule.

Platten’s Fish and Chips

This Norfolk-based restaurant participated in the UK trial. Unlike office workers who can skip meetings, restaurant staff must be physically present. Platten’s solved this by analyzing their quietest times and rotating shifts differently. They found that staff were more energetic and provided better customer service, which offset the scheduling complexity.

Bolt

The checkout technology company Bolt implemented a four-day workweek independently of these specific academic pilots but reported similar results. In their internal surveys, 94% of employees wanted to continue the program, and 86% reported they were more efficient with their time.

How Companies Maintained Productivity

You might wonder how employees achieved 100% output in 20% less time. The trials revealed that the reduction in hours forced necessary operational changes.

Participants reported the following adjustments:

  • Meeting reduction: Companies cut default meeting times from one hour to 30 minutes.
  • Focus time: Teams implemented “no-interruptions” blocks where Slack and email were turned off.
  • Process automation: Motivation to finish early drove employees to automate repetitive tasks they previously tolerated.

The reduction in hours acted as a forcing function. It eliminated the “performance theater” where employees look busy but achieve little.

Frequently Asked Questions

Does the 4-day workweek mean working 10 hours a day?

No. The pilots discussed here utilized a 32-hour workweek model. The goal is to reduce total hours worked, not compress 40 hours into four days, which often leads to fatigue.

Did any companies drop out of the trials?

In the UK trial, nearly every company completed the pilot, and 92% opted to continue. However, a small number of firms paused or stopped the experiment. This usually happened in companies that did not plan their coverage shifts adequately or had sudden leadership changes during the pilot.

Yes, it is legal for a company to offer full-time pay for 32 hours of work. Currently, federal law (the Fair Labor Standards Act) requires overtime pay after 40 hours. There is no legal penalty for working fewer hours. Legislators like Senator Bernie Sanders have introduced bills (The Thirty-Two Hour Workweek Act) to lower the standard workweek, but companies can voluntarily adopt this schedule right now.

Does this work for client-facing businesses?

Yes. Client-facing businesses in the trials, such as marketing agencies and consultancies, typically used a “staggered” model. Instead of closing the office on Friday, half the team took Monday off and the other half took Friday off. This ensured coverage five days a week while every individual worked only four.