Rural out-migration is a common phenomenon in mountainous regions of the world, often leading to depopulation and various socio-economic challenges. In the Indian Himalayan Region, the state of Uttarakhand and Himachal Pradesh exhibit a contrasting pattern of rural out-migration despite having similar geographical and climatic conditions. On the one hand, Uttarakhand has experienced large-scale permanent out-migration, resulting in many ghost villages, on the other hand Himachal Pradesh has just experienced temporary out-migration with limited negative impacts. The study investigates the key drivers behind these differences, focusing on policy frameworks, governance structures, resource accessibility, and socio-cultural attitudes of people toward migration. A mixed-methods approach was employed to conduct the study. Both quantitative and qualitative data were used. The data were collected from household surveys and government reports. The quantitative data were complemented by qualitative insights from focus group discussions and in-depth interviews. The comparative analysis of the both states revealed that differences in local governance, economic structure and opportunities, and state policies significantly influence migration patterns in both the states. The findings of the study contribute to the existing migration literature and provide evidence-based recommendations for policymakers to mitigate the adverse impacts of migration while leveraging migration for sustainable mountain development in the region. Besides, this research offers critical insights into addressing one of the most pressing challenges in the mountainous regions of the world.