Red Bull is encouraging bosses to give their staff an early start to the weekend, with thousands expected to take up the offer and head to the pub with friends, head home early or make the most of the extra leisure time.
The energy drinks firm claims will improve productivity by encouraging people to work smart so they can leave their desks early.
Red Bull said: “#4pmFinish isn't about slacking off, it's about being more productive.
"That's why we've surveyed a range of experts – including a scientist, an ex-sports star and a range of successful entrepreneurs – for their tips on clearing your in-tray.”
There may be some science behind the publicity stunt, with previous studies showing the benefits of six-hour work days.
Experts have claimed the move to a shorter working day could boost productivity and happiness.
Staff at Oxford University’s Sleep And Circadian Neuroscience Institute have also carried out research, which seems to support a more relaxed working approach – saying a 9am clock-on is at odds with our internal body clocks and it would be better for staff to begin work at 10am.