Emergency Medical Dispatch Centers (EMDCs) serve as critical gatekeepers in the provision of prehospital emergency care and the coordination of patients who may require hospital admission. This study aims to examine and characterize the trends in emergency calls to EMDCs in Bangkok. This population-based study was conducted using a dataset of 275,747 calls to EMDCs throughout Bangkok during a three-year study period from January 1, 2020, to December 31, 2022. Most of the 264,219 eligible regional emergency calls came from Zone 6: Nopparat Rajathanee Hospital (65,661 calls, 24.85%), whereas the lowest number of calls came from Zone 2: Klang Hospital (7,663 calls, 2.9%). The greatest proportion of calls concerned unknown problems (27.5%), followed by traffic accidents (19.6%), dyspnea (10.4%), unconsciousness (9.6%), and fall injuries (8.1%). Calls for emergency priority level II (60.87%) cases peaked in the morning (07:00–10:00) and evening (15:00–18:00), at similar times of day. Calls for dyspnea (37.1%), a life-threatening condition, peaked in the morning (06:00–09:00). The most frequent cause of trauma-related emergencies was traffic accidents (19.6%), which peaked in the evening (16:00–22:00), and mainly occurred from September to December. This study reveals significant temporal variations in the demand for emergency ambulance services across hospital catchment areas in Bangkok, reflecting dynamic needs within the urban population. By identifying the most frequent emergency conditions by time of day, the findings provide critical insights for disaster preparedness, resource optimization, and the development of time-sensitive response strategies within the emergency medical service system.

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