We evaluate the 1968 H3N2 Flu pandemic´s economic cost in a cross-section of 52 countries. Using excess mortality rates as a proxy for the country-specific severity of the pandemic, we find that the average mortality rate (0.0062% per pandemic wave) was associated with a decline in output of 2.4% over the two pandemic waves. Our estimates also suggest the losses in consumption (-1.9%), investment (-1.2%), and productivity (-1.9%) over the two pandemic waves. The results are robust across regressions using alternative measures of mortality and output loss. The study adds to the current literature new empirical evidence on the economic consequences of the past pandemics in light of the potential impacts of the Covid-19 pandemic on productivity.