The time spent is virtually unchanged from 2007 — actually one minute longer, according to a report from the office released on Monday.
The figures indicate that full-time Swiss employees have work weeks that are close to the average for the European Union.
Numbers from the UK’s Office of National Statistics from 2011 showed full-time workers in Austria and Greece put in the longest weeks in the EU at around 43.7 hours, followed by those in the UK (42.7 hours).
Denmark had the shortest week with an average of 39.1 weeks.
The Swiss statistics show that the contractual period of work fell by two minutes in 2012 to 41 hours and 47 minutes from 2007.
This figure is different from the actual number of hours worked because it includes the average period of weekly absences (1 hour, 34 minutes, down by a minute) offset by overtime (one hour, 11 minutes, up two minutes).
According to a survey of the population, the average length of annual holidays for full-time workers increased from 4.9 weeks in 2007 to five weeks in 2012.
The tendency over the past 15 years has been for longer holiday periods in Switzerland, the statistics office said.
Average annual holidays in 1996 were 4.6 weeks, the office said.
The oldest full-time workers, those aged 50 to 64, enjoyed the longest holidays (5.5 weeks in 2012), compared to 4.8 weeks for those aged 20 to 49.