The pilot, which involved 17 companies, ended with a 100% success rate.
All of the companies that took part have decided to continue working a shorter working week at the end of the trial.
One chief executive praised the pilot and said they “expect that most organisations will be doing this in the next 10 years”.
New four-day working week trial has perfect success rate
The six-month trial began last November and was organised by the 4 Day Week Foundation.
According to a report on the trial, organisations involved were able to maintain service levels and key performance indicators whilst observing several benefits for employee wellbeing.
It added that almost two-thirds of workers registered a reduction in how often they experienced burnout.
Meanwhile, two in five found an improvement in their mental health and almost half said they felt more satisfied with life.
Joe Ryle, campaign director of the 4 Day Week Foundation, said: “With greater knowledge, expertise and experience of what it takes to successfully implement a four-day week, we’re really pleased to see such a high success rate.
“People are happier, businesses are thriving, and there’s no turning back.
🚨NEW PILOT LAUNCH🚨
This Autumn, join the movement that’s redefining the future of work.
Start date: Thursday 25th September 🗓️
Our annual UK Four-Day Week Pilot has successfully supported hundreds of companies to move to a four-day week.
Find out more via the link below ⬇️ pic.twitter.com/OE5medrzbb
— 4 Day Week Foundation (@4Day_Week) June 2, 2025
“We’ve proved it again and again: a four-day week works and should now be implemented more widely across the economy.”
Bron Afon Community Housing has 420 staff and is extending its pilot further.
Chief executive Alan Brunt said: “Almost as soon as we started talking about it, our teams got together to set about making it work, which was brilliant.
“We’ve closely monitored our performance and customer satisfaction. We’re happy with the results so far and will continue to make sure we’re delivering for our customers.
“I expect that most organisations will be doing this in the next 10 years or so.”
Will the UK have a four-day work week?
Ongoing discussions and trials surrounding the four-day work week in the UK are continuing; however, the Government has previously ruled out immediate plans for a nationwide, mandated four-day work week.
The Department for Business and Trade said last year: “We have no plans to impose a four-day working week on employers or employees.”
Despite this, Deputy Prime Minister Angela Rayner has voiced support for a four-day working week.
The 4 Day Week Foundation is a group that leads the UK’s national campaign for a four-day working week.
They are pushing for a four-day, 32-hour working week, meaning no loss of pay for workers.
Would you like to see a four-day working week? Let us know in the comments.
