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Background The prevalence of unruptured intracranial aneurysms globally is ~3% and incidence of rupture is 8-10 per 100,000 per year. Aneurysmal scoring models exist to assess rupture risk and council patients, three of which are the International Study of Unruptured Intracranial Aneurysms (ISUIA) criteria, PHASES score, and the unruptured cerebral aneurysm study (UCAS). The purpose of this study was to investigate the characteristics of ruptured aneurysms at Vermont’s principal academic referral center and apply scoring models to assess their potential at predicting rupture risk.Methods 10 year single institution retrospective study (2014-2024) of first time aneurysmal subarachnoid hemorrhage (aSAH) with DSA-confirmed culprit aneurysms. All patients were stratified by ethnicity, age, gender, size and location of aneurysm, aspect ratio, history of hypertension and smoking, presence of aneurysmal calcification and daughter sac, and multiplicity of aneurysms. Individual PHASES risk, ISUIA score, and UCAS risk were calculated and those aneurysms with a low predictive risk profile were subsequently sub-analyzed.Results 160 patients with confirmed aSAH were identified from a parent list of 326 patients carrying a diagnosis of non-traumatic SAH. Notably, a total of 60 out of 160 (38%) had a five-year rupture risk score of 0 per ISUIA. 85 out of 160 (53%) had a theoretical five-year rupture risk of ≤1.3% with corresponding PHASES score ≤5. 86 out of 160 (54%) had a theoretical one-year rupture risk of ≤1% per UCAS. For aneurysms in these ‘low risk’ classification, the majority were located in the AComm/A1-2 complex, mean height was 4mm and the average aspect ratio was 1.8 vs. 2.2 for the entire cohort.Conclusion The majority of patients with ruptured aneurysms would have been characterized as harboring low-risk aneurysms based on available popularized scoring systems. When assessing rupture risk, analyzing other factors such as aneurysm morphology and aspect ratio should be considered. Scoring systems should be used with caution when managing patients with unruptured aneurysms, especially for those with small unruptured aneurysms (<7mm).Disclosures E. Wicks: None. L. Silveira: None. C. Norton: None. S. Gregorek: None. E. Delahmetovic: None. B. Tranmer: None. B. Liebelt: None.