Later this year, over thirty UK companies will take part in a six-month trial of a four-day workweek with no loss of pay. They will be following the 100-80-100 model, where workers get 100 percent of the pay for 80 percent of the time, while theoretically delivering 100 percent of the efficiency of a five-day workweek.

The British experiment comes after a trial in Iceland between 2015 and 2019, where this new approach was taken up by public sector employees. It was described as an “overwhelming success.” Employees had a much better work-life balance and were found to be just as or sometimes more productive than under longer working hours. Since the trial, 85 percent of workers in Iceland now either work or have the option to work a four-day week with no loss of pay.

The trial in the UK will be led by the 4 Day Week Global campaign in partnership with the think tank Autonomy and researchers at Oxford University, Boston College, and Cambridge University. Campaigners say the introduction of a four-day week can bring benefits not only to employees’ mental and physical welfare but also profitability gains for companies. Other positive impacts, they say, include environmental benefits, increasing time for hobbies and life administration, helping connect families, reducing unemployment and underemployment, and even saving the high streets.