Objectives: To adapt the Self-Care of Heart Failure Index V6.2 to Portuguese and analyze self-care capability in maintenance, management and self-confidence in patients with heart failure attending nursing care services at two Portuguese hospitals. Method: Exploratory study, sample of 110 patients who attended the nursing care service for patients with heart failure at two Portuguese hospitals, carried out over a six-month period. Descriptive statistics and psychometric tests were used. Results: Internal consistency similar to the original scale. The patients consisted mostly of older adults with low self-care literacy, low values associated with physical activity and salt control in meals taken outside the home, and inadequate control of signs and symptoms. Conclusion: Patients present difficulties in maintenance and management of the disease, and are self-confident regarding it. This instrument enables individualized assessment leading to decision-making and adjusted action