Climate change, extending beyond its environmental impacts, is triggering large-scale population movements and placing increasing pressure on health systems. The displacement of millions of people due to extreme weather events, drought, and rising sea levels heightens the demand for health services in both sending and receiving regions, while deepening infrastructure inadequacies, workforce shortages, and financing problems. In fragile areas such as Bangladesh, Somalia, and the Pacific Islands, health infrastructure is approaching a point of collapse, whereas in Europe the long-term resilience capacity is being strained. Climate-induced migration alters the geographical distribution of infectious diseases, accelerating the spread of cholera, typhoid, malaria, and dengue fever. Moreover, the trauma and uncertainty experienced by migrants lead to an increase in mental health problems and expand the need for psychosocial services. This situation poses a threat to the sustainability of health services, particularly in low- and middle-income countries. Future projections indicate that by 2050, 216 million people will be at risk of climate-related migration. In this context, according to the Shared Socioeconomic Pathways (SSP) framework, current global trends align with a hybrid SSP3–SSP4 scenario characterized by weak international cooperation and deepening social inequalities. Under this scenario, climate migration has the potential to evolve not only into an increased patient burden but also into a systematic health crisis involving governance and justice dimensions. In conclusion, effectively managing the impacts of climate migration on health systems requires migrant-inclusive policies, climate-resilient health infrastructure, a strengthened health workforce, data-driven governance, and robust global solidarity mechanisms. This holistic approach emerges as a fundamental necessity for building resilient and equitable health systems for the future.