Background Sleep inertia is a debilitating state of reduced physical and mental drive upon awakening, typically lasting less than 30 min, but symptoms can persist for several hours in susceptible individuals. Objectives This research aims to observe whether Portuguese firefighters experience and manage sleep inertia and its symptoms during emergency activations, while also exploring potential differences between volunteer and professional firefighters. Materials and methods A qualitative study was conducted through interviews with 30 firefighters, including both professional (n = 17) and volunteer (n = 13) firefighters. The sample comprised firefighters of both genders (n = 17 and 13, men and women, respectively) with an average age of 41.87 years. Results It was observed that, although direct strategies for managing sleep inertia were not implemented in either volunteer or professional fire services, the majority developed indirect strategies to mitigate its effects. Discussion It is crucial for these strategies to be rapidly implemented without compromising emergency response times, and for firefighters to recognize and address sleep inertia without stigma. Conclusions Considering the differences between professional and volunteer firefighters, it is essential to investigate methods to mitigate the negative effects of sleep inertia, especially for those working in shifts, without resorting to substances harmful to health.