Spiritual well-being is a crucial aspect of holistic development for seminarians since it shows how they feel about God and their sense of purpose in life. This research sought to assess the spiritual well-being of seminarians in the Diocese of San Carlos, Philippines, concentrating on their religious and existential dimensions. Using a quantitative research design, data were gathered from 73 seminarians using the Spiritual Well-Being Scale (SWBS). Descriptive statistics were used to examine the responses. The results show that most seminarians had good spiritual health. In fact, 89.0% said they had excellent religious health, and 82.2% had great existential health. In general, 83.6% of the seminarians who took part showed that they were spiritually well, which means that they keep a good balance between their belief system and their own purpose. The research finds that spiritual development within the diocese efficiently nurtures seminarians’ whole spiritual well-being. These results have ramifications for seminary formation, underscoring the need for ongoing support and tailored pastoral care to maintain and enhance the spiritual well-being of the future clergy in the Diocese of San Carlos, Philippines.