State universities and colleges (SUCs) in the Philippines are increasingly adopting ISO 9001:2015 by the International Organization for Standardization (ISO) to enhance their organizational performance. However, maintaining the quality management system (QMS) beyond initial certification presents significant challenges, including deviations from compliance and lack of sustained resource support. This research seeks to explore the integration and long-term sustainability of ISO 9001:2015 within SUCs, with a particular focus on extension services. Using a descriptive case study approach, data were gathered through interviews, document analysis, and field observations conducted in two SUCs located in Region III. The research not only identifies the benefits like improved service delivery and satisfying stakeholders, but it also recognizes the hindrances that include the reluctance to change and resource mobilization. The study concludes that indeed the QMS has a positive impact on the performance of an organization, but at the same time, its continuity depends on the uninterrupted support as well as the involvement of relevant stakeholders (Sartor et al., 2019). These findings account for the broader conversation on quality management (QM) in higher education institutions (Al-Bashir, 2016) and how proper strategic planning is the key to meeting the long-term goals of the institution.