IntroductionThe length of stay (LOS) in psychiatric hospitals is regularly used as an indicator of inpatient care efficiency and quality indicator. Psychiatric hospitalizations have been linked to a variety of clinical and patient-related factors. The objectives of this study were to assess the duration of stay in psychiatric hospital in Lebanon and to evaluate the LOS associated factors.MethodsA five years retrospective study was conducted at the Psychiatric hospital of the Cross between January 2018 and December 2022. Data on hospital admissions was obtained from medical files and the LOS was defined as the time in days elapsed between the admission and discharge date as noted in the medical file.ResultsThe mean duration of the global length of the stay was 28.35 ± 26.57 days, with a range between 2 and 300 and a median of 21.00 days. Being diagnosed with schizophrenia (Beta = 10.25), having a public insurance (Beta = 4.09) and having an intermediate social status (Beta = 3.45) were significantly associated with higher length of stay. Being a female (Beta = − 5.15), married (Beta = − 3.94) and older age (Beta = − 0.17) were significantly associated with lower length of stay.ConclusionThe importance of social factors should be highlighted, as they are necessary components of patients’ wellbeing and may facilitate the decision of discharge. Being single, male gender and a diagnosis of schizophrenia were associated with a longer stay at the psychiatric hospital. Further studies are needed to explore the clinical implication of the factors related to LOS in order to identify patients with a higher probability for prolonged hospitalization, to plan necessary interventions for these specific situations.