Aim: To report all-cause and PE related short term mortality by clinical severity of PE and to identify any missed opportunities for thrombolysis. Background: Mortality related to pulmonary embolism varies widely in the reported literature even for the same clinical severity category of PE. Method: Electronic medical records of all patients presenting to a large tertiary care teaching hospital in London, between October 1, 2018, and January 16, 2020, who had a discharge diagnosis of acute pulmonary embolism were reviewed retrospectively. Results: There was no PE related mortality in the low-risk PE group. There was one PE related death in the submassive PE group (1.47% mortality on day 14 and day 30).  Massive PE was associated with a 29.4% PE related mortality short-term mortality.