Background: Information about the availability and accessibility of diagnostics and treatments for heart failure (HF) is sparse. The aim of this study was to describe the gaps in the diagnosis and treatment of HF in member countries of the Asian Pacific Society of Cardiology using an online survey. Methods: A cross-sectional observational study was conducted among medical professionals practising in member countries of the Asian Pacific Society of Cardiology who provide care to patients with HF. The participants answered an English online self-administered questionnaire. Results: The study included 257 respondents from 26 countries or regions. The majority of respondents (58%) responded that 50% or fewer of their patients would have natriuretic peptide levels checked during the hospital stay. More than half of the respondents (52%) said that more than 50% of their patients had access to transthoracic echocardiography. For mineralocorticoid receptor antagonists, angiotensin receptor–neprolysin inhibitors and sodium–glucose cotransporter 2 inhibitors, the proportion with access was 86%, 84% and 81%, respectively. Conclusion: Healthcare professionals in the Asian Pacific Society of Cardiology member countries identified substantial gaps in the availability of diagnostic and therapeutic interventions for HF in their areas of practice. Natriuretic peptide testing was less available than transthoracic echocardiography, which is the primary diagnostic modality for HF in the region. At least 10% had no access to mineralocorticoid receptor antagonists, angiotensin receptor–neprolysin inhibitors or sodium–glucose cotransporter 2 inhibitors in their centres.