Protected area (PA) connectivity in transboundary regions enhances ecotourism potential by linking biodiversity-rich areas, fostering conservation, and supporting local economies. In such settings, shared cultural and natural resources create opportunities for transboundary ecotourism, benefiting communities on both sides. Strengthening connectivity, PAs promotes sustainable tourism and encourages collaborative conservation efforts, driving socio-economic development while preserving ecological and cultural heritage in the Khangchendzonga Landscape (KL). Realising the importance, the current study explores the potential for ecotourism development in the surrounding villages of two important Indian protected areas (PAs)—Singalila National Park (West Bengal) and Barsey Rhododendron Sanctuary (Sikkim). Both PAs are part of a transboundary region shared between India and eastern Nepal, characterised by deep sociocultural ties. The villages in this transboundary zone are fragmented and largely dependent on the PAs, emphasising the need for enhanced connectivity to create an ecotourism corridor that can improve the socio-economic conditions of local communities and ensure biodiversity conservation. Drawing on Participatory Rural Appraisal (PRA) techniques, household surveys conducted in seven villages, and secondary literature, this study reveals that ecotourism in and around these PAs is necessary and an opportunity to support rural livelihoods and promote biodiversity conservation. The research outcomes propose community-based strategies for promoting, managing, and developing ecotourism, ensuring long-term benefits for local communities and contributing to ecological conservation. Further, the study advocates for stronger interstate (West Bengal and Sikkim) and transboundary (India and Nepal) collaborations to enhance the socio-ecological value of the region. In addition, the result findings support assisting policymakers in developing appropriate policies based on local perspectives, ensuring long-term benefit-sharing, and promoting community-led activities within the targeted landscape while initiating transboundary ecotourism between India and Nepal.