The optimal setting for initiating subcutaneous foslevodopa/foscarbidopa (CSFLI) in advanced Parkinson's disease remains debated. This study aimed to compare six-month clinical outcomes according to initiation setting. We conducted a retrospective cohort study of consecutive patients with advanced Parkinson's disease started on CSFLI in either an outpatient or inpatient setting. Baseline demographics and clinical measures were recorded. Outcomes at six months included motor complications (MDS-UPDRS Part IV), motor severity (MDS-UPDRS Part III), non-motor impact and quality of life, treatment parameters and levodopa equivalent daily dose, treatment simplification to CSFLI monotherapy, and safety. Group comparisons used standard statistical tests with two-sided significance. Thirty-six patients were included: 21 outpatients (58.3%) and 15 inpatients (41.7%). Six-month motor and quality-of-life outcomes were broadly similar between groups. The inpatients group showed higher MDS-UPDRS Part IV scores at six months (10.3 vs. 7.7, P=0.039) despite comparable baseline Part IV values. Infusion parameters and CSFLI levodopa-equivalent dosing at six months were comparable between groups. CSFLI monotherapy was achieved in more than 80% of patients in both groups with minimal use of concomitant oral levodopa. Adverse events were similar, and no serious events occurred. Early CSFLI outcomes appear largely independent of initiation setting when protocols are structured and follow-up is rigorous. Higher six-month Part IV scores in inpatients likely reflect post-initiation factors rather than baseline severity. Outpatient initiation emerges as a viable, resource-sparing option. Prospective studies with standardized assessments are needed to test causality and refine patient selection.