Indoor environmental quality (IEQ) plays a key role in determining occupants’ productivity at work; however, the analyses in the interconnected factors among building physical, attitudinal, social and demographic components in one study are lacking. To link this research gap, this study investigates these interconnected factors’ influence on occupants’ IEQ-productivity belief, defined as personal subjective evaluation on the linkage between the impacts of five IEQ aspects (the qualities of indoor temperature, air, natural and electric lighting and acoustics) and productivity. A cross-sectional survey data is collected in university offices from six countries (Brazil, Italy, Poland, Switzerland, Taiwan and the U.S.). Results of multiple linear regression model indicate that IEQ satisfaction is the strongest positive predictor of the IEQ-productivity belief; this relationship is stronger in private offices. Country of residence is the second primary predictor. Several attitudinal-behavioral factors, including thermal comfort, perceived ease of controlling indoor environmental features, attitudes toward sharing controls, and are all positively associated with IEQ-productivity belief. Interestingly, the level of control accessibility to light switches has the strongest impact on as opposed to other controls. On the other hand, group norms and conformity intention were not significant predictors. Regarding demographics, men are more likely to perceive the IEQs has positive impacts on their productivity than women without considering other variables in the regression model; on the contrary, women are more likely to consider all IEQs as having positive impacts on productivity than men, after considering other variables. Our findings provide suggestions in helping prioritize wellness in workplaces.