Reports on occupant behavioral adaptation to varying thermal conditions in India are limited. We analyzed the data from our thermal comfort survey of 2787 occupants in 28 office buildings (N=6048): 13 mixed mode (MM), 14 completely air-conditioned and one naturally ventilated building in Chennai and Hyderabad. Behavioral adaptation was found to be vital for thermal comfort. Occupants adaptively used air-conditioners and or fans in MM buildings during the temperature excursions. Our logistic regression predicts 89.4% and 28.5% of air conditioners to be operating in MM buildings in Chennai and Hyderabad respectively, at 29 degrees C of outdoor daily mean temperature. Females, young subjects, and people with low body mass index had higher comfort temperatures than males, older people, and obese occupants respectively, with a difference of 0.3-1.0 K in various groups, which is significant at 95% confidence interval. In naturally ventilated environments females were comfortable at 28.5 degrees C and men at 27.8 degrees C. Women accepted the environments better. Many behavioral control actions were noted throughout the year without much seasonal shifts. Staying in airy place was the most prominent behavioral adaptation all through. This reinforces the need for elevated air movement indoors. (C) 2015 Elsevier B.V. All rights reserved.