The global prevalence of heart failure (HF) is rising and carries a heavy social and economic burden. Type 2 diabetes mellitus (T2DM) patients are at an increased risk of incident HF even in the absence of cardiovascular risk factors. Patients with established HF are at an increased risk of death following a worsening HF event. Various trials on sodium-glucose cotransporter-2 (SGLT2) inhibitors have shown that these novel drugs prevent incident HF and reduce the risk of worsening HF in both patients with T2DM and those without diabetes. This literature review analyzed the data from 13 randomized controlled trials that met the pre-specified inclusion criteria. The aim was to compare the clinical outcomes of SGLT2 inhibitors for primary and secondary prevention of HF in patients with T2DM and those without diabetes. In addition, this study collated and summarized the patients’ clinical characteristics with respect to the clinical outcome, and finally, it evaluated the safety considerations when using SGLT2 inhibitors. The data showed that SGLT2 inhibitors are effective and safe in the primary and secondary prevention of HF across a broad spectrum of patient populations and care settings. Therefore, wider eligibility for their use should be considered.