Objective: To gain insight into the process of postpartum care utilisation and in-home support among vulnerable women. Design, method, participants and setting: A qualitative interview study was conducted among 23 pregnant and postpartum vulnerable women in the Netherlands, following a grounded theory approach. Women were determined as vulnerable by their healthcare providers. Theoretical sampling of participants was applied and was alternated by data analysis to include information-rich cases until saturation was achieved. Results: A conceptual framework of postpartum care utilisation was generated consisting of three phases: pregnancy, early postpartum period and late postpartum period. Within these phases, information provision, parenting self-efficacy and social network were identified as overarching themes. Perceived inadequate information on content of postpartum care posed a major barrier to forming realistic expectations during pregnancy and hindered its utilisation. Low self-efficacy facilitated postpartum care utilisation. All women experienced increased self-efficacy during and after postpartum care. Support from a social network influenced expectations regarding the added value of postpartum care during pregnancy, and lowered actual utilisation during the postpartum period. The costs of postpartum care and the role of the maternity care assistant acted as general barriers or facilitators influencing the three overarching themes and therefore postpartum care utilisation indirectly. Conclusions: Our findings suggest that postpartum care utilisation among vulnerable women may be improved by considering the particular phase and relevant themes applying to individual women, and adapt care accordingly. We recommend to provide comprehensive, understandable information and to emphasise the gains of postpartum care in improving self-efficacy for vulnerable women. Moreover, involving a woman's social network in postpartum care may add value to this care for this population.