Heart failure (HF) and cancer are leading causes of global morbidity and mortality that share a significant bidirectional relationship. Epidemiologic studies reveal that cancer patients and survivors face a substantially elevated risk of HF, largely driven by cardiotoxic systemic therapies including chemotherapy, targeted therapy, immunotherapy and radiation therapy. Conversely, individuals with HF have a markedly increased incidence of cancer. This interconnection is underpinned by age and shared modifiable risk factors, including smoking, hypertension, diabetes and obesity, as well as common pathophysiological mechanisms such as chronic inflammation, neurohormonal activation, oxidative stress and dysregulated angiogenesis. Clonal haematopoiesis of indeterminate potential has emerged as a novel biological link, promoting both maladaptive cardiac remodelling and tumourigenesis. Clinically, the coexistence of HF and cancer creates complex management challenges, as each condition worsens the prognosis of the other and limits therapeutic options. In addition to providing a broad overview of the topic, this review incorporates three aspects that are underexplored in existing cardio-oncology literature-management of advanced metastatic cancer in patients with HF, use of advanced HF therapies in patients with cancer and disparities in cardio-oncology care and clinical trial representation. Effective management of patients with HF and cancer requires a multidisciplinary cardio-oncology approach that incorporates rigorous risk stratification, early detection using serial cardiac biomarkers and imaging and personalised management tailored to cancer treatment. Irrespective, cancer patients with HF have a poor prognosis. It is necessary to balance oncological efficacy with cardiovascular safety while providing a clear definition of the goals of care. Early integration of palliative and rehabilitative care can significantly improve patient quality of life and outcomes. Nevertheless, effective novel treatment strategies have significantly improved the overall survivorship for patients with cancer and/or HF.