In Productivity: Meryn Stol voted up an answer. Balaji Viswanathan About 22C/71F as per multiple independent research. In my personal experience, most work places are often colder than this. There is a steeper drop in productivity when things are colder than the ideal. So, if you have to err, err on the side of warmth. Room temperature and productivity in office workImpacts of Indoor Environments on Human Performance and Productivity Which temperature is best for your productivity?The effects of air temperature on office workers’ well-being, workload and productivity-evaluated with subjective ratingsImpacts of Indoor Environments on Human Performance and Productivity See question on Quora - Meryn Stol