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Small (≤ 5 mm) intracranial aneurysms include both ruptured and unruptured lesions with markedly different early outcomes. Data on in-hospital mortality across this spectrum remain limited, particularly in Latin America. This study aimed to evaluate in-hospital mortality and identify factors associated with mortality in patients with small intracranial aneurysms, stratified by rupture status. This retrospective multicenter observational study included 1,519 patients with small (≤ 5 mm) intracranial aneurysms managed between 2017 and 2023 across eight centers in five Latin American countries. Patients were analyzed as an overall cohort and stratified by rupture status: 421 (28%) presented with aneurysmal subarachnoid hemorrhage and 1,098 (72%) had unruptured aneurysms. The primary outcome was in-hospital mortality. Clinical and treatment-related variables associated with in-hospital mortality were evaluated using Cox proportional hazards models. Overall in-hospital mortality was 7%, with a marked difference between patients with ruptured and unruptured aneurysms (18% vs. 3%). Management was endovascular in 69%, microsurgical in 11%, and conservative in 20%. In the overall cohort, factors independently associated with in-hospital mortality included age > 65 years, prior subarachnoid hemorrhage, rupture at presentation, treatment-related complications, and medical complications. In patients with ruptured aneurysms, mortality was primarily associated with hemorrhage severity and acute complications, whereas mortality in patients with unruptured aneurysms was low and was primarily associated with treatment-related factors. Differences in outcomes according to antiplatelet therapy were observed but should be interpreted cautiously because of potential confounding by indication. In-hospital mortality differed substantially according to rupture status in this multicenter Latin American cohort of patients with small intracranial aneurysms. Mortality in patients with ruptured aneurysms was primarily associated with hemorrhage severity and acute complications, whereas mortality in patients with unruptured aneurysms was lower and was primarily associated with treatment-related factors. These findings should be interpreted in the context of the retrospective observational design and potential treatment-selection bias.