This study investigates the impact of the intense usage of air-conditioning systems on the thermal comfort requirements of building occupants. It compares the thermal comfort requirements of building occupants in Iraq and Gulf Cooperation Council (GCC) countries. Iraqis have limited usage of air-conditioning units, whilst people in GCC countries intensely operate these systems. Research work underpinning this article involved undertaking a year-long thermal comfort survey in Iraq, and an intensive analysis of thermal comfort studies conducted in GCC countries. Results show that, in Iraq, people experience a 2–50 °C annual indoor temperature range, and their annual comfort range is 14–35 °C. In GCC countries, due to the intense usage of air-conditioning systems, the widest recorded annual indoor temperature range is 17.2–31.0 °C, and the widest annual comfort range is 20.0–27.8 °C. These results demonstrate the significant impact of air-conditioning systems on narrowing the thermal comfort limits of building occupants leading to high energy consumption. This study presents a novel comparison between two cases highlighting the impact of air-conditioning systems on the thermal comfort requirements of building occupants. The results of this study can be used to inform the development of thermal comfort standards that better consider people’s adaptation capabilities to help reduce energy consumption for heating and cooling purposes.