As of March 1, 2020, the mortality rate of COVID-19 was estimated at 3.6% in China and 1.5% outside China based on the number of deaths relative to confirmed cases. However, these estimates may underestimate the actual mortality rate because they do not account for asymptomatic or mild cases that were not tested. The authors re-estimated the mortality rate by dividing the number of deaths on a given day by the number of confirmed cases 14 days prior, resulting in a higher rate of 5.6% in China and 15.2% outside China. Global mortality rates over time, adjusted for a 14-day delay, leveled off at 5.7%. A recent study suggests that the mortality rate in Wuhan could be as high as 20%. These findings indicate that the current figures might underestimate the potential threat of COVID-19 in symptomatic patients.As of March 1, 2020, the mortality rate of COVID-19 was estimated at 3.6% in China and 1.5% outside China based on the number of deaths relative to confirmed cases. However, these estimates may underestimate the actual mortality rate because they do not account for asymptomatic or mild cases that were not tested. The authors re-estimated the mortality rate by dividing the number of deaths on a given day by the number of confirmed cases 14 days prior, resulting in a higher rate of 5.6% in China and 15.2% outside China. Global mortality rates over time, adjusted for a 14-day delay, leveled off at 5.7%. A recent study suggests that the mortality rate in Wuhan could be as high as 20%. These findings indicate that the current figures might underestimate the potential threat of COVID-19 in symptomatic patients.