The prevalence and mortality of heart failure (HF) increase with age. As a result, the early diagnosis of HF in this population is useful to reduce cardiovascular morbidity and probably mortality. However, the diagnosis of HF in the elderly is a challenge. These challenges arise from the under-representation of elderly patients in diagnostic studies and clinical trials, the increasing prevalence of HF with relatively normal ejection fraction, the difficulty in accurate diagnosis, the underuse of diagnostic tests, and the presence of co-morbidities. Particularly in the elderly, symptoms and signs of HF may be atypical and can be simulated or disguised by co-morbidities such as respiratory disease, obesity, and venous insufficiency. This review aims to provide a practical clinical approach for the diagnosis of older patients with HF based on the scarce available evidence and our clinical experience. Therefore, it should be interpreted in many aspects as an opinion paper with practical implications. The most useful clinical symptoms are orthopnoea and paroxysmal nocturnal dyspnoea. However, confirmation of the diagnosis always requires further tests. Although natriuretic peptides accurately exclude cardiac dysfunction as a cause of symptoms, the optimal cut-off level for ruling out HF in elderly patients with other co-morbidities is still not clear. In our opinion, echocardiography should be performed in all elderly patients to confirm the diagnosis of HF, except in those cases with low clinical probability and a concentration of brain natriuretic peptide (BNP) or N-terminal proBNP (NT-proBNP) lower than 100 or 400 pg/mL, respectively.