A survey of the 3,000 staff that took part, found the majority of this time (52%) was spent working, 14% was spent on family time, 16% on extra sleeping, 12% on relaxation and 6% on commuting elsewhere.
Just under nine out of 10 (88%) of people that took part in the flexible working pilot thought that they were at least as productive as normal, over a third (36%) claimed to have been more productive, only 125 people needed to work from the office that day - only 109 cars entered the car park (against 1,100 on an average day) and only 1 person in the whole of O2 HQ didn't know anything about the flexible working pilot and consequently arrived for work.
On 8 February 2012, O2 conducted the experiment, asking the entire workforce in its head office to work away from the office for the day.
Employees based at O2's Slough HQ - a quarter of its 12,000-strong workforce - participated in the pilot, operating remotely for the day as the doors were shut and lights turned off at the business' 200,000 sq ft office.
The pilot aimed to push the boundaries of what is possible through flexible working and has underpinned O2's contingency plans to manage expected travel disruption and delays during the summer's Olympic Games.
The facts speak for themselves. More than 2,500 people successfully worked away from the office, with only 125 mission-critical staff left in the building.
Thanks to newly strengthened networks and upgraded collaboration technology, everyone who needed to get online and communicate was able to do so. The post pilot poll found 88% of staff said that they were at least as productive as on a normal day at the office, with 36% claiming to have been more productive.. In line with the company's ambitious three year sustainability plan, the experiment also benefitted the environment, with approximately 12.2t of CO2eq saved.
O2 continues to believe that the initiative sends a clear signal to its employees, business customers and other UK organisations on the advantages of working flexibly and one of the key drivers of the flexible working pilot was to research and share the results of the day.
Ben Dowd (pictured), business director for O2 said, "Line managers are used to managing people they can see. Managing them remotely is a completely different thing. Our Pilot on 8 February didn't solve all of those problems, but it is a good start. We can do a lot more to support line managers in charge of remote teams, but we know it's not going to happen overnight. We're educating people about the whole future of work here and there's still work to be done, but we're pleased to say this is a fantastic start".
O2's flexible working day may have revolved around a single point in time but its results have implications across much bigger timescales.
O2's electricity consumption decreased by 12% on February 8th. This was not as dramatic as the 53% decrease in water usage, but a significant number nonetheless.
In combination with the reduction in CO2 emissions achieved by the commuting cuts, 2,000 hours of travel time was saved. These numbers represent a very substantial all-round benefit to the environment and to the company's energy costs. This is the equivalent of an average of 45 minutes per employee.
O2 employees saved nearly £9,000 on the day primarily through reduced commuting costs.
Perhaps inevitably, the sustainability issue around flexible working is more complicated than it might at first appear. Paradoxically, for example, gas usage in the building increased slightly - probably due to the loss of body heat in the building.
Dowd added: "The success of O2's experiment extends much further than just allowing some of the workforce to stay at home and work. It proves that with the right thinking and planning, even the largest organisations can protect themselves from the most severe disruptions to their business. It shows that given the right preparation and communication, conservative presenteeism-based attitudes to work can be changed, with great benefits for both managers and staff. It shows that businesses really can make significant and lasting reductions to their environmental impact, in a multitude of areas.
"Above all though, it demonstrates that the principles underlying flexible working really are the principles that will build the future of work, and determine the way that people, technology and buildings interact in the decades and centuries ahead. O2 is using these principles now, to build tomorrow's businesses today."
It is hoped that the pilot will also showcase the wider economic business case for flexible working in helping to drive efficiency, productivity and innovation. O2 has previously saved over £3 million in overheads through such measures. These learnings will be applied in line with the company's ambitious three year sustainability plan, in which O2 pledges to help over 125,000 business employees work flexibly, and collectively save over 500,000 miles of travel and over 160,000 thousand tonnes of carbon emissions.
The initiative marks the latest phase in O2's flexible working journey, following in the footsteps of previous efforts. These include O2's Tomorrow's Workspace initiative, which saw the business consolidate its operations into a single campus in Slough. By enabling the workforce to be more mobile, O2 achieved a 53 per cent reduction in its carbon footprint and despite having the same number of people HQ is now operating with 550 fewer desks.