Religiosity has been widely recognized as a positive contributor to happiness and psychological well-being across cultures. Although religiosity and spirituality are conceptually distinct, religious practices such as prayer and meditation often enhance spiritual experiences—particularly within India's diverse religious landscape. While previous studies have explored the mechanisms linking religiosity and well-being, findings remain mixed. Gratitude, highly revered in most religious traditions, has consistently shown positive associations with both religiosity and flourishing. It may serve as a bridge between religiosity and well-being by fostering a stronger sense of connection and community support. Recent developments in gratitude research emphasize its transcendental or transpersonal dimension—acknowledging benefits from sources beyond the self or without a specific benefactor. This perspective may better explain the mediating mechanism between religiosity and flourishing than traditional dispositional gratitude focused on interpersonal exchanges. The present study investigates the mediating role of transpersonal gratitude in the relationship between religiosity and flourishing among a multireligious Indian sample (N = 241). Participants completed the Centrality of Religiosity Scale-7 (CRS-7), Transpersonal Gratitude Scale (TGS), and The Flourishing Scale. Using a cross-sectional design and snowball sampling, we hypothesize that transpersonal gratitude will mediate the positive association between religiosity and flourishing. Additionally, differences across major religious groups (Hindus, Christians, and Muslims) will be explored to assess the robustness of the relationships and the contextual relevance of transpersonal gratitude. Findings are expected to inform culturally sensitive interventions promoting gratitude-based well-being in religious contexts.