Objective. To estimate the proportion of deaths in confirmed cases according to altitude categories (low, medium, and high), and to evaluate a possible association between altitude and COVID-19 mortality in Colombia during the first two waves of the pandemic. Methods. Cross-sectional, analytical study. Adults residing in Colombia during 2020, with microbiological confirmation of SARS-CoV-2 infection were included. We calculated CFR using a binomial confidence interval, dividing altitude in three categories. We also performed a logistic regression model to evaluate the association between altitude and COVID-19 mortality. Results. Data on confirmed cases of COVID-19 during the period from March 06, 2020, to December 15, 2020, reported in 1,112 municipalities in Colombia were analyzed. A total of 994,738 confirmed cases were reported, including 32,034 deaths (0,03%). The mean age of cases w...