Tourism is pivotal for rural economic development; however, despite hosting a substantial number of tourists, many developing countries with rural landscapes face persistent poverty among local communities. This study aims to delve into the impact of tourism (geoheritage and national parks) on local livelihoods, examining drivers for livelihood portfolio and community decisions to engage in tourism activities. The Multivariate Probit and instrumental variable models (Instrumental Variable Probit, and Two Stage Least Squares) were employed on data from 582 respondents collected through cross-sectional questionnaires. Results highlight the significant influence of socioeconomic factors—sex, age, household size, credit access, market access, social membership, and education—on livelihood portfolio. Results show that specific tourism activities, such as accommodation services, handcrafts, catering and hospitality, and tour guiding, exert varying effects on household food security, income, and access to essential social services. Challenges hindering participation include education levels, information and awareness, service quality, cultural barriers, financial costs, government policies, competition, resource monopolisation, corruption, and infrastructure deficiencies. Recommendations include investments in skill development, infrastructure enhancement, cultural preservation, financial inclusion, regulatory frameworks, and community awareness programs. These strategies aim to facilitate household participation in tourism activities, promoting geotourism and enhancing the well-being of Mount Kilimanjaro National Park communities. Policymakers are urged to implement these measures to uplift local livelihoods and foster sustainable tourism in the region.