Transitioning to adulthood is a fundamental yet challenging phase in human development. Despite its relevance, the literature has paid little attention to the impact that transitioning to adulthood has on multiple aspects of individual well‐being. This is one of the few attempts that has employed a sequential explanatory mixed‐methods study to explore how the path to adulthood impacted on the psychological and overall well‐being of Italian young adults. In the quantitative phase, we employed two‐step cluster analysis to assign 45 young adults, who had completed the Italian I COPPE scale of multidimensional well‐being, to three clusters based on their level of change in psychological and overall well‐being. Results from mixed design ANCOVA revealed that participants belonging to the high change cluster showed the highest significant positive change over time with respect to well‐being. In the qualitative phase, 17 individuals took part in focalized narrative interviews, which aimed at exploring significant events, barriers, and facilitators, which had impacted on their well‐being during the transition to adulthood. The textual material was analysed through the Grounded Theory Methodology. It emerged that the state of transition was associated with some triggering events and a temporary negative impact on the interviewees' well‐being. However, findings also revealed that people assigned to different clusters had put in place or learned several resources, skills, and copying strategies, which led to different transitional and well‐being outcomes.