Aims Due to insufficient evidence and a lack of cohesive guidelines, the management and use of fluid restriction in patients with heart failure (HF) may vary among healthcare professionals. However, the extent of this variation is unknown. The aim of this study was to describe physicians' and registered nurses' (RN) clinical practice regarding fluid intake and fluid restriction in adult patients with HF. Methods and results Physicians and RNs treating patients with HF at 75 hospitals across all healthcare regions in Sweden were invited to answer a web-based survey regarding management on fluid intake and fluid restriction. Data were analysed with descriptive statistics and chi-square test. A total of 646 physicians and RNs across 45 hospitals in Sweden completed the survey. Significant differences in recommendations and management were found in relation to professional role, care setting and work experience. Overall, 93.8% recommend fluid restriction for all or some patients with HF. RNs recommend fluid restriction for all patients with HF to a significantly higher extent compared with physicians (34.5% vs. 14.9%; P < 0.001). Additionally, 49.2% believe that fluid restriction is an effective treatment strategy to prevent congestion, and 29.3% recommend fluid restriction routinely. One-third lacked knowledge of existing local guidelines regarding fluid restriction. Conclusions This study shows that there are differences in clinical practice regarding healthcare professionals' recommendations on fluid intake and fluid restriction. These differences may result in patients with HF receiving varied and inconsistent care. Recommendations were primarily based on each healthcare professional's individual opinion rather than on evidence and guidelines.