Informal care provision is an integral part of the long-term care system. However, it has been shown to have negative effects on the carers’ economic activity, and understanding the mechanisms behind this is crucial for social policy design. This study provides new insight into mid-life carers’ decisions to reduce their economic activity through a convergent mixed-methods design. Quantitative analysis of a sample of 2,233 carers aged fifty from the National Child Development Study (NCDS) Wave 8 with follow up at age fifty-five, and qualitative analysis of in-depth interviews of forty-eight carers between 2008-2010, were used. The combined results indicate that being female, single never married, having financial issues, being an employee, and frequently meeting a parent are associated with economic activity reduction; the carers’ own perspectives further elucidate key factors, such as their value and identity, family structure, life course events, and care intensity, which affect their decisions.