Lifelong learning policies have expanded opportunities for adults to upskill and reskill, yet, entering higher education (HE) as a mature student is a process intertwined with life circumstances and structural barriers. Drawing on Careership theory, this study explores how HE becomes conceivable and actionable for mature students and which routines and turning points shape their pathways to HE. We conducted semi-structured interviews with nine mature students (aged 35–56) enrolled in undergraduate programmes at a Swedish university. Data were analysed using reflexive thematic analysis. The findings identify three distinct yet overlapping pathways to HE: reskilling after disruption, eligibility through detours, and late migration. Across pathways HE became conceivable through accumulated educational and work experiences, reshaping participants’ horizons for action. For HE to become actionable, both formal eligibility (i.e. qualifications) and practical eligibility (e.g. access to financial support) were required, making eligibility an important structural lever. Pathways to HE also involved a re-negotiation of self-understandings, often facilitated by municipal adult education.