Higher education institutions (HEIs) primarily serve as centers of knowledge, capacity builders, and policy influencers and choose to voluntarily engage with the United Nations Sustainable Development Goals (UN-SDGs) as they are not mandated to implement them. In this paper, we examine the role of Saudi Arabian higher education institutions (HEIs) in sustainability efforts through their participation in the Times Higher Education Impact Rankings (THE IR) from 2019 to 2024. Also, the strategic alignment of HEIS with sustainability frameworks is assessed, emphasizing their contributions beyond ranking participation. Using the European University Association (EUA) and the UN-KSA Cooperation Framework (2022-2026), this study identifies both achievements and strategic gaps in HEIs' contributions. Additionally, a comparative analysis with the Saudi Arabian Sustainable Development Report (SDR) of 2024 explores HEIs broader contributions. Hierarchical Cluster Analysis (HCA) is applied to classify HEIs based on SDG engagement, identifying leading, partnering, and supporting HEIs for potential collaboration. The findings reveal a significant increase in HEI participation, rising from 4% in 2019 to 49% in 2024. However, persistent gaps exist, particularly in SDGs 1-2 and 12-15 (addressed by fewer than 10% of HEIs) and SDGs 7, 9-11, and 16 (targeted by fewer than 25% of HEIs). This study highlights the need for a structured strategic alignment beyond rankings, positioning HEIs as enablers of sustainability driven education, research, and institutional governance.