BACKGROUND: A low-sodium diet is a core component of heart failure self-care but patients have difficulty following the diet. AIM: The aim of this study was to identify predictors of higher than recommended sodium excretion among patients with heart failure. METHODS: The World Health Organization Five Dimensions of Adherence model was used to guide analysis of existing data collected from a prospective, longitudinal study of 280 community-dwelling adults with previously or currently symptomatic heart failure. Sodium excretion was measured objectively using 24-hour urine sodium measured at three time points over six months. A mixed effect logistic model identified predictors of higher than recommended sodium excretion. RESULTS: The adjusted odds of higher sodium excretion were 2.90, (95% confidence interval (CI): 1.15-4.25, pp=0.007) for patients with diabetes; and 2.22 (95% CI: 1.09-4.53, p=0.028) for patients who were cognitively intact. CONCLUSION: Three factors were associated with excess sodium excretion and two factors, obesity and diabetes, are modifiable by changing dietary food patterns.