This study seeks to assess whether and to what extent caregiver work strain is ameliorated by the presence of additional family caregivers and formal service use. Building on the stress process model and stress-appraisal moderation, we examine how formal and informal support varies in associations with caregiver distress for men and women. This study utilizes data provided by the National Study of Caregiving, which is linked with care-recipient information from the National Health and Aging Trends Study. Using panel methods for the pooled waves, we estimated caregiver outcomes of emotional well-being on the intersection of experiences of work strain and (a) the number of additional caregivers and (b) utilization of 6 different types of formal support. Additional informal caregivers for each respective care recipient are associated with lower levels of distress, although utilization of formal services (paid help and Medicaid funding) is positively associated with caregiver distress. Informal support can offset the impact of work strain, but interactions are only evident for women caregivers. The findings suggest that informal support, exemplified by the number of additional caregivers, corresponds with reduced emotional distress among employed caregivers and can mitigate the negative impacts of work strain. However, positive associations between formal support and male and female caregiver distress suggest that the context of formal services may offer limited or untimely support. This study is expected to broaden our understanding of informal caregiving in later life and provide practical implications on how to sustain informal care.