Initially intended as an adjunct treatment for type 2 diabetes mellitus (T2DM), SGLT2-inhibitors (SGLT2i) have transformed into an unexpected pillar of the heart failure (HF) regimen. The past several years have witnessed a meteoric rise of this drug class, starting with the serendipitous results of trials assessing the safety of the glucose-lowering therapy in a broad range of cardiovascular patients and culminating with the demonstration of a reduction in hospitalizations for heart failure and cardiovascular mortality in dedicated heart failure populations. The heart failure benefits of SGLT2i are independent of a patient’s glycemic status, but the salient mechanisms of cardioprotection remain a subject of robust debate and ongoing research. Cardiologists as well as physicians of other disciplines should become familiar with the main indications, benefits, and clinical consideration of implementation. In this review, we will discuss the advance of SGLT2i in heart failure, ranging from the results of large randomized clinical trials to potential mechanisms of action.