Financial wellbeing is an important component of people's overall wellbeing, reflecting the capacity to live a comfortable and fulfilling life. Yet virtually nothing is known about this topic for autistic people. This study addressed this gap using a two-phase sequential mixed-methods design. Here, we report on findings from the Phase 2 qualitative study. In this study, 21 autistic participants were purposively selected based on the status of their financial wellbeing, including 12 people with high, and 9 with low, financial wellbeing, and interviewed by an autistic researcher. We identified four themes through reflective thematic analysis. Having access to a stable income made an enormous difference to people's financial wellbeing. Participants emphasised how their broader social supports, especially family support, shaped their financial wellbeing. Yet, planning financially was often challenging, especially for people who had insufficient money to meet their basic needs. Nevertheless, our participants reported a strong drive to stay in control and avoid unnecessary risk. Our findings revealed how much money matters in autistic people's lives. Future research should investigate the ways in which autistic people could secure more reliable incomes and identify the most effective ways to support them to achieve financial resilience.