Patients with alcohol-related diagnosis in emergency departments (ED) are at high risk of readmission. Evidence shows an association between alcohol related admissions and a wide range of diseases and disorders. Understanding the risk factors for readmission and the asso-ciation with length of stay in the ED may help identify those who would benefit from targeted interventions. Thus, the hypothesis of this study is that patients with alcohol-related diagnoses and a short length of stay in the ED have a higher risk for readmission. Therefore, this study aimed to investigate the association between length of stay in the ED and 30-day readmission for patients with alcohol-related acute admissions as well as to uncover possible risk factors for 30-day read-mission. The study used a retrospective cohort design and was carried out from March 1, 2019, to January 31, 2020. The inclusion criteria were ≥ 18 years, admitted to an ED, and having an alcohol-related primary or secondary diagnosis (based on ICD-10 codes). Patients were fol-lowed for 30 days after discharge from initial hospitalization to identify associations between length of stay and 30-day readmission. We included 1,174 patients and found that 17% (95% CI: 15-20) of the patients admitted with an alcohol-related primary or secondary diagnosis were readmitted within 30 days. The hazard ratio (HR) for readmission increased with length of stay when compared to admission ≤ 24 hr; admission > 24-48 hr HR 1.50 (95% CI: 1.08-2.08), admission > 48 hr HR 2.08 (95% CI: 1.23-3.52). The study revealed that patients with alcohol-related diagnoses were at a higher risk of ED readmission the longer they stayed in the ED. Furthermore, the risk of readmis-sion increased if patients had a medical or psychiatric diagnosis prior to admission or lived alone.