Lower gastrointestinal bleeding (LGIB) is a frequent cause of emergency department (ED) consultation, leading to investigations but rarely to urgent therapeutic interventions. The SHA ₂ PE score aims to predict the risk of hospital-based intervention, but has never been externally validated. The aim of our single-center retrospective study was to describe patients consulting our ED for LGIB and to test the validity of the SHA ₂ PE score. We included 251 adult patients who consulted in 2017 for hematochezia of <24 h duration; 53% were male, and the median age was 54 years. The most frequent cause of LGIB was unknown (38%), followed by diverticular disease and hemorrhoids (14%); 20% had an intervention. Compared with the no-intervention group, the intervention group was 26.5 years older, had more frequent bleeding in the ED (47% vs. 8%) and more frequent hypotension (8.2% vs. 1.1%), more often received antiplatelet drugs (43% vs. 18%) and anticoagulation therapy (28% vs. 9.5%), more often had a hemoglobin level of <10.5 g/dl (49% vs. 6.2%) on admission, and had greater in-hospital mortality (8.2% vs. 0.5%) (all p < 0.05). The interventions included transfusion (65%), endoscopic hemostasis (47%), embolization (8.2%), and surgery (4%). The SHA ₂ PE score predicted an intervention with sensitivity of 71% (95% confidence interval: 66-83%), specificity of 81% (74-86%), and positive and negative predictive values of 53% (40-65%) and 90% (84-95%), respectively. SHA ₂ PE performance was inferior to that in the original study, with a 1 in 10 chance of erroneously discharging a patient for outpatient intervention. Larger prospective validation studies are needed before the SHA ₂ PE score can be recommended to guide LGIB patient management in the ED.