What have four-day work week trials actually found about productivity?

Trials of the four-day work week have generally found that productivity either remains stable or improves, rather than declining as many feared.

Here is a summary of what those studies have consistently shown:

• Maintained or Increased Output: In the largest trials, such as the 2022 pilot program coordinated by 4 Day Week Global in the UK, the vast majority of participating companies reported that productivity levels were maintained. Many reported that output actually increased because staff were more focused and meetings became more efficient.
• Reduced "Dead Time": When hours are compressed, employees tend to cut out low-value activities—such as excessive meetings, long breaks, or unproductive digital distractions—to ensure their work is completed within the shorter timeframe.
• Improved Employee Wellbeing: Research consistently shows significant reductions in employee burnout, stress, and sick leave. This leads to higher retention rates and lower recruitment costs, which indirectly boosts overall organizational productivity.
• Increased Focus: With a shorter work week, employees often report feeling more "recharged," which helps them maintain a higher intensity of focus during their working hours compared to a traditional five-day schedule where energy levels often dip toward the end of the week.

Important Context: These findings are most consistent in "knowledge work" or office-based environments. The impact on service, retail, or manual labor sectors can be more complex, as those roles are often tied directly to customer-facing hours or physical output, requiring different staffing models to maintain coverage.

If you are interested in a specific industry or a particular trial report (such as the 2022 UK study or the Icelandic trials), let me know, and I can look into the specific data for those cases.