9-1-1 telecommunicators are frequently exposed to indirect traumatic events that impact their mental and physical health and are often required to work overtime with rotating shifts. Previous studies reported various harmful effects of overtime on the health and well-being of workers, such as musculoskeletal injuries, burnout, low job satisfaction, fatigue, and intent to leave. However, there is limited research on the impact of overtime hours on 9-1-1 telecommunicators' stress symptoms, especially mandatory overtime hours. This study aimed to examine the relationship between overtime hours-mandatory and voluntary-and the level of stress symptoms among 9-1-1 telecommunicators. We used secondary data from the surveys of the "Multi-tasking to hyper-tasking: Investigating the impact of Next Generation 9-1-1" study for analysis. Linear mixed-effects regression was applied to examine the association of overtime hours with the stress level. Of the 403 participants, 47.6% reported that they were required to work mandatory overtime, and the mean mandatory overtime was 7.51 (SD = 12.78) hours in the past month. 58.3% reported working voluntary overtime, and the mean voluntary overtime was 11.63 (SD = 17.48) hours. This study found that mandatory overtime hours were associated with an increase in self-reported stress symptoms (β = 0.30, p = .002), whereas no significant association was found between voluntary overtime and the level of stress symptoms (β = -0.01, p = .885). Study results highlight the importance of reducing mandatory overtime in call centers as one possible strategy for reducing stress levels among this critical workforce.