Background Increasing attention has been paid to the survival of endometrial cancer (EC) patients, but the non‐cancer causes of death from EC are rarely reported. This study primarily aimed to investigate the non‐cancer causes of death in patients with EC. Methods The study collected relevant data, including age, tumour stage and treatment mode, on patients diagnosed with endometrial malignancies from 2000 to 2015 in the Surveillance, Epidemiology, and End Results (SEER) Programme. We analysed the standardised mortality ratio (SMR) to determine the cause of death. Results The study included 135,831 patients with EC. During the follow‐up, 46,604 (34.3%) patients died, of whom 42.9%, 15.6% and 41.5% died of EC, other cancers and non‐cancer causes, respectively. As the diagnosis time increased, the number of EC‐associated mortalities gradually decreased. The most common non‐cancer causes of death were heart disease, cerebrovascular disease and diabetes. Regarding the general population of the United States, patients with EC died of heart disease (SMR: 1.06; 95% confidence interval [CI]: 1.03–1.09), diabetes (SMR: 1.56; 95% CI: 1.47–1.65) and septicaemia (SMR: 1.40; 95% CI: 1.28–1.52), which were statistically significant. Conclusions For patients with EC, the number of deaths from non‐cancer causes (mainly heart disease, cerebrovascular disease and diabetes mellitus) is equivalent to that of EC. In addition, compared with the general population, EC survivors have a higher risk of death from sepsis and diabetes. These discoveries support how survivors can avoid future‐related health risks. By doing this, clinicians can improve the quality of life and chances of the survival of patients with EC.