BACKGROUND: Sepsis remains a leading cause of mortality, especially among patients admitted to non-ICU settings like intermediate care units (IMCUs). Current prognostic tools have limitations in predicting outcomes in these patients. This study aimed to identify key predictors of mortality using decision tree analysis. METHODS: We conducted a prospective observational study from January 2023 to June 2024, enrolling 254 septic patients admitted to the IMCU of Santorso Hospital, Italy. Clinical, laboratory, and demographic data were collected, and decision tree analysis was performed to identify factors associated with 30-day mortality. Variables were compared using univariate and multivariate analyses, and significant predictors were incorporated into the decision tree model. RESULTS: The 30-day mortality rate was 14.6%. Serum albumin was identified as the root node of the decision tree, with lower levels (≤2.3 g/dL) strongly associated with mortality. Additional predictors were identified as higher NEWS scores (OR 1.153, CONCLUSIONS: Serum albumin is a key prognostic marker in septic patients admitted to IMCUs, alongside NEWS and age. These findings suggest that albumin levels at admission may aid in early risk stratification and clinical decision-making in non-ICU environments. Future studies should validate these results across different healthcare settings to optimize sepsis management.