BACKGROUND: Caregiver contributions (CC) to heart failure (HF) self-care maintenance (ie, CC to maintaining HF stability) and management (ie, CC to dealing with HF signs and symptoms) improve patient outcomes, but it is unknown whether caregiver preparedness influences CC to self-care and whether caregiver confidence mediates this process. OBJECTIVES: We evaluated the influence of caregiver preparedness on CC to HF self-care maintenance and management and the mediating role of caregiver confidence. METHODS: This is a secondary analysis of the MOTIVATE-HF study. Patients were 18 years or older, with a diagnosis of HF in New York Heart Association classes II to IV, who had insufficient self-care and did not have severe cognitive impairment. Patients' informal caregivers were those people inside or outside the family who gave most of the informal care to the patients. We used the Caregiver Preparedness Scale and the Caregiver Contribution to Self-Care of HF Index. We tested a path analysis model and the indirect effects. RESULTS: Caregivers (n = 323) were 55 (SD, 15) years old on average and predominantly female (77%). The path analysis showed that higher scores in caregiver preparedness were associated with higher scores in caregiver confidence. In turn, higher caregiver confidence was associated with higher CC to self-care maintenance and management. Caregiver confidence mediated the association between caregiver preparedness and CC to self-care maintenance and management. CONCLUSIONS: Caregiver confidence may play a role in CC to self-care. Interventions to improve CC to HF self-care should not only be focused on improving caregiver preparedness but also should consider the role of caregiver confidence.