By Mari Hansen The staff of Solidsense, an event planning firm with no particular notoriety other than volunteering for an odd experiment, stopped working on Fridays in a bright, open-plan office in Stuttgart. Not every now and then. Every Friday. for half a year. After the trial was over, their co-founder Sören Fricke stated, “I don’t want to work on Fridays anymore,” in a direct manner that no press release would have dared. I simply don’t. In actuality, Friday is now the third day of the weekend. You only work when there is no other choice. Buried in a Bloomberg report on the trial’s outcomes, that quote provides more insight into the actual outcomes of Germany’s largest four-day workweek experiment than the majority of the official data.
The six-month pilot, which was coordinated by the nonprofit 4 Day Week Global and the Berlin-based management consultancy Intraprenör, involved 45 businesses from 13 different industries and was closely observed by researchers from Münster University. Workers received their full salary while working fewer hours, though the precise number of fewer varied significantly amongst participants. Julia Backmann, the scientific lead, used more than just self-reported satisfaction surveys. In addition to distributing smartwatches to monitor daily stress minutes, heart rate, sleep quality, and physical activity, the team also collected hair samples to measure cortisol. Compared to most workplace studies of this type, which usually ask participants how they feel and call it data, the methodology was more rigorous.
Key information — Germany’s four-day workweek trial 2024
| Trial overview | Six-month pilot involving 45 German companies across 13 industries — employees worked fewer hours with no reduction in salary, running February to October 2024 |
| Organizers | Berlin-based management consultancy Intraprenör, in collaboration with nonprofit 4 Day Week Global (4DWG) — monitored by researchers from Münster University |
| Scientific lead | Julia Backmann, Münster University — used hair samples, smartwatches, and fitness trackers to measure stress, heart rate, activity levels, and sleep quality alongside standard surveys |
| Productivity outcome | Employees remained as productive as during a five-day week — in some cases productivity rose between 1% and 3% despite reduced hours; two-thirds reported fewer distractions due to streamlined processes |
| Meeting culture shift | Over half of participating companies redesigned meetings to be less frequent and shorter — one in four companies adopted new digital tools to increase workplace efficiency |
| Health findings | Participants slept an average of 38 extra minutes per week and were more physically active — significant improvements in mental health and reduced burnout symptoms confirmed by smartwatch data |
| Unexpected findings | Monthly sick days dropped only slightly — a statistically insignificant change; no measurable environmental benefit from reduced commuting, as some employees used longer weekends for travel |
| Continuation rate | 73% of participating companies said they were prepared to make the change permanent or extend the experiment — a two-year follow-up study published February 2026 confirmed 70% continued with some form of reduced hours |
| Design limitations | Only about a third of the 41 evaluated companies actually reduced hours by a full day — roughly half cut less than 10% of weekly hours; critics noted self-selection bias among participating firms |
| Employer skepticism | Steffen Kampeter, CEO of Germany’s Employers Association BDA, argued that a four-day week with full pay amounts to a major effective wage increase that most companies cannot afford long-term |
Depending on your priorities, what they discovered was either comforting or subtly amazing. Productivity was maintained. Despite the decrease in hours, it actually rose by 1% to 3% in a subset of businesses. Because procedures had been actively streamlined to make the shorter workweek feasible, two out of every three employees reported fewer distractions. More than half of the businesses changed their meeting schedules to be shorter and less frequent. One in four people started using new digital tools that they had never used before. Experienced managers will see a pattern here: the four-day workweek did not simply eliminate one day. It made businesses consider, perhaps for the first time in years, which aspects of the workweek were truly productive and which were just time wasters.
Compared to the productivity figures, the health findings were clearer. During the trial, participants were measurably more physically active and slept an extra 38 minutes a week on average. Symptoms of burnout were reported less frequently. Unlike other studies of this type, smartwatch data supported the self-reported reductions in stress levels rather than contradicting them. The businesses themselves noticed that employees seemed to feel better, according to the researchers.
The two-year follow-up study, released in February 2026, is starting to investigate whether that translates into long-term retention, lower recruitment costs, and the kind of quiet organizational stability that doesn’t show up in quarterly metrics. By then, 70% of participating organizations had maintained reduced hours in one way or another, which is not the result of a botched experiment.
And yet. The skeptics don’t just make convenient arguments; they have valid ones. Speaking from the Institute for Employment Research, labor market researcher Enzo Weber brought up a methodological issue that is hard to ignore: businesses that sign up for four-day workweek trials are, by definition, already in favor of the concept. They are not an accurate representation of the German economy, which employs workers in hundreds of industries, including manufacturing, logistics, healthcare, and construction, where it is difficult to reduce five days of physical or shift-based labor into four.
The fact that the trial had trouble recruiting participants in the first place says something about how most German employers view the idea. The CEO of the German Employers Association, Steffen Kampeter, bluntly characterized the arrangement as a significant effective wage increase—the same output, the same pay, but less time—and contended that most businesses operating in international markets, where cost competitiveness is real and immediate, could not absorb that cost indefinitely.
Even the researchers were taken aback by some of the findings. In contrast to comparable trials in the UK and Iceland, where reductions were more noticeable, monthly sick days only slightly decreased. More surprisingly, there was no discernible environmental benefit. Other nations had discovered that reducing commutes and closing offices entirely for a single day resulted in quantifiable energy savings. Longer weekends in Germany caused some employees to travel, negating any potential carbon footprint reduction. Giving people more free time and having them use it in ways that don’t always match the presumptions of those who created the policy is a minor irony.
Whether the four-day workweek can expand beyond the knowledge-work, service-sector businesses that dominated this trial is still up for debate. The truthful portrayal of Germany’s actions is more limited than what the headlines imply. Not a guide. Not evidence that the five-day workweek is just inefficiency disguised as custom. However, carefully gathered evidence suggests that, for a particular set of organizations, the Friday that is eliminated may have been doing less than everyone thought, and that, when people actually think about it, what takes up the remaining four days may be more than sufficient.