Sustainability has turned into a critical focus for businesses, drawing considerable interest from the commercial sector and scholarly environments. While empirical investigations have been conducted regarding sustainability reporting within small and medium enterprises, only a limited number of companies are subjected to increased pressure to adopt sustainability reporting practices, thereby ensuring enhanced transparency and disclosure in their financial and sustainability disclosures. This research, framed by Institutional Theory, delves into how challenges in sustainability reporting obstruct organizations from properly evaluating and sharing their progress on sustainability aims. With an explanatory research framework in place, we circulated survey questionnaires to 400 participants, who were randomly drawn from a population of 28,927 registered SMEs in Metro Manila, Philippines. The application of Interpretative Structural Modelling and MICMAC Analysis revealed that the absence of regulatory frameworks, governmental assistance, and sustainability infrastructure constitutes the most critical obstacles impacting other determinants. In contrast, neither the deficiency in sustainability awareness nor the inadequacy of training and skills demonstrated a considerable impact on the other identified barriers. This study clarifies the complex interactions and interrelations among the obstacles to sustainability reporting, thus providing significant perspectives for organizations aiming to overcome these difficulties. The findings suggest that business leaders and stakeholders can formulate targeted strategies and interventions to facilitate the adoption of sustainability reporting practices within organizations. The application of the institutional theory framework highlights that pressures arise from a diverse array of institutional actors, including regulators, customers, and local communities, which collectively shape corporate behavior and reporting methodologies.