Modern cancer care is characterized by a focus on organ-sparing multi-modal treatments. In the case of non–muscle-invasive bladder cancer this is particularly true; treatment is focused on reducing the frequency of low-risk recurrences and preventing high-risk progression. Deep regional hyperthermia is an oncologic therapeutic modality that can help achieve these two goals. The combination of hyperthermia with chemotherapy and radiotherapy has improved patient outcomes in several tumor types. In this review, we highlight the biology of therapeutic fever-range hyperthermia, discuss how hyperthermia is administered and dosed, demonstrate how heat can be added to other treatment regimens, and summarize the data supporting the role of hyperthermia in the management of bladder cancer.