Understanding the perspectives of incarcerated persons on health and illness, as well as the social contexts influencing these perspectives, is important for developing healthcare interventions that effectively address their specific needs and improve overall well-being. The aim of this study was to explore and understand the complex, multi-dimensional experiences of health and illness among incarcerated persons within the Slovenian correctional system. This study employed an interpretative descriptive design. Using purposive sampling, ten incarcerated persons—five females and five males—were invited to individual, face-to-face, semi-structured interviews. Thematic analysis was conducted in accordance with the interpretative description analytical process. Four major themes were identified: (1) Perspectives on health and illness during incarceration, (2) Healthcare access and self-care during incarceration, (3) Social contacts and their impact on health, and (4) Programmes and activities to enhance well-being. The findings highlighted a shift in perception among participants from a traditional view of health as merely the absence of illness to a more dynamic and holistic understanding, encompassing physical, mental, and social determinants of health. The structured environments within prisons can sometimes paradoxically improve physical health by promoting positive health behaviours, yet they often exacerbate mental health challenges due to restricted freedom and social isolation. The study's implications are significant for policy-making, suggesting that integrated health strategies can significantly improve health outcomes for incarcerated populations, aligning with public health objectives and ensuring better community reintegration.