Healthcare renunciation has been a recent focus of the public health debate, but large-scale investigations of healthcare renunciation are scarce. The goal of this study was to examine healthcare renunciation among young adults at French universities. It investigated prevalence of and reasons for healthcare renunciation and identified subgroups of vulnerable youths. Data were collected in the 2013 triennial study conducted by the French National Observatory of Student Life. That study had a sample of 35,810 18- to 25-year-old participants. Measures included healthcare renunciation, reasons for healthcare renunciation, demographics, cultural and socioeconomic background, health and social outcomes, healthcare system-related variables, and markers of adulthood. The results showed that the prevalence of healthcare renunciation was 27.2%. The most common reasons for healthcare renunciation were refusal renunciation (self-care, 12.7%; wait for improvement, 15.5%) and barrier renunciation (financial reasons, 12.1%; lack of time, 10.2%). Therefore, healthcare renunciation is linked not only to financial constraints but also to individuals' subjective needs and ways of facing illness. Overall, disadvantaged youths and youths transitioning to adulthood were likelier to renounce care, especially for financial reasons. To conclude, there are social inequalities in the use of healthcare by emerging adults in higher education in France. Emerging adulthood appears to be a risky period in which people are likely to renounce healthcare for multiple reasons. Support should be provided for vulnerable youths to prevent them from becoming increasingly vulnerable.