ObjectivesThis study aimed to assess the incidence of inappropriate hospital stay and to identify the reasons behind inappropriate hospitalisation.MethodsThis retrospective cohort study included patients admitted in the General Internal Medicine Unit, Sultan Qaboos University Hospital, Muscat, Oman, from January to June 2020. The average length of hospital stay for all included patients was calculated. The appropriateness evaluation protocol technique was used to examine admissions that exceeded the average length of hospital stay; subsequently, the reasons for the inappropriate hospital stay were identified.ResultsThere were 855 admissions during the study period. In this cohort, 53.1% were male and the median age was 64 years (interquartile range [IQR]: 44–75 years). There was a total of 6,785.4 hospitalisation days and the average length of hospital stay was five days (IQR: 3–9 days). A total of 31.8% of admissions (n = 272) and 9.9% of hospitalisation days (n = 674 days) were classified as inappropriate. Delay in complementary tests (29.0%) and unavailability of extra hospital resources (21.7%) were identified as the most common reasons associated with inappropriate hospital stays. Old age was associated with increase in inappropriate hospital stay.ConclusionA significant proportion of hospitalisation days were inappropriate due to hospital-related factors. Therefore, auditing hospital services and investing in home-based care are among the top strategies that are likely to improve early discharge and minimise inappropriate hospital bed occupancy.