Company bosses that gave all their staff a four-day week say the move has improved morale and productivity - and that any doubters should give it a go.
The idea of working four days out of seven, with the other three off, is building pace in the UK.
Companies such as Morrisons and Canon are letting some staff take part in a trial of the new rota being monitored by academics at the universities of Cambridge and Oxford.
But digital marketing company Reboot Online is already so impressed by the results of its own four-day week trial that it is making it permanent for all staff.
Reboot joint managing director Naomi Aharony said: "It’s something we had been mulling over for a little while and through research found that countries such as Iceland had already successfully trialled a four-day week without any detriment to productivity, and in some cases it had increased productivity.
"We wanted the four-day week to reduce stress and re-energise people, which in turn would help improve performance at work and staff morale."
Is your firm trialling a four-day week? Message mirror.money.saving@mirror.co.uk
The firm started giving staff three days off a week in October 2021.
Employees worked from Monday to Thursday, then took Friday to Sunday off - like having a bank holiday every single week.
Reboot joint managing director Shai Aharony said Reboot staff were excited for the trial, but had some doubts too.
Some were worried that a shorter working week would mean increasing their stress levels by cramming five days' work into four.
Others were concerned the new system would hit their clients and their performance targets.
"These were considered and monitored meticulously throughout the trial," Shai added.
But the benefits far outweighed the negatives, and the system is now permanent.
Shai said: "Productivity has increased, but it is still early days so will continue to monitor this regularly. Creativity forms a huge part of our work and we have seen a healthy increase here.
"We carried out an anonymous employee survey and we found one in five employees had a better work/life balance and one in six had started to learn or enhance a skill, increase fitness, or take up a hobby."
Some of the negatives were that time-sensitive emails could be missed if they were sent on a Friday - but Reboot has now put a system in place so that this doesn't happen.
Critics of a four-day week often say it leads to staff being lazy and harms businesses overall.
British productivity has been low for years , puzzling policymakers and experts. Some say working fewer days will only worsen this, while others think it would help.
But the Reboot bosses say the doubters should try the new working pattern before bashing it.
Naomi said: "You should try it before being critical. It is true it might not suit every company or business model, but for Reboot it has worked."
"If you asked me to pick one benefit out of all the stats and numbers that I’m most proud of, it’s the fact that the process of moving to a four-day week has demonstrated our intense belief in our staff and reciprocating that faith with even greater work than before.
"The four-day week has now been integrated into the company from Jan 2022 and I believe more companies will follow this route."