Fragmented care prompted Rwanda to introduce a national policy mandating the integration of sexual and reproductive health (SRH) and HIV services in primary healthcare clinics. Evidence on the implementation outcomes of such policies at the primary care level in sub-Saharan Africa remains limited. This study evaluated the implementation outcomes—specifically acceptability, adoption, and feasibility—of the national integrated SRH/HIV policy within primary care clinics in Kigali, Rwanda. A concurrent mixed-methods design was employed. Quantitative data were collected via a cross-sectional survey of 150 healthcare providers across 30 purposively selected primary clinics. Qualitative data were gathered through 20 in-depth interviews with clinic managers and policy implementers. Data were analysed using descriptive statistics and thematic analysis. Policy adoption was high, with 87% of clinics reporting structural integration of services. However, significant feasibility challenges were identified, primarily due to inadequate staffing and persistent stigma, which hindered client-centred care. Acceptability among providers was moderate but varied by service type. The national policy has been largely adopted structurally, but its successful implementation is constrained by systemic resource limitations and attitudinal barriers. Integration remains more operational than transformative at the point of care. To strengthen implementation, policymakers should invest in targeted training to address stigma and revise clinic staffing models. Future programmes must move beyond co-location to ensure integrated, person-centred service delivery. Service integration, implementation science, HIV, sexual and reproductive health, primary healthcare, Rwanda This study provides empirical evidence on the implementation gaps of a national integration policy, offering practical insights for policymakers and programme managers aiming to strengthen integrated SRH/HIV care in similar settings.