We compiled criteria pollutants from four air quality monitoring stations in Bogotá, eight in Santiago, and five in São Paulo to characterize the impact of emission changes on air quality during the early Coronavirus-imposed lockdown. Time series include hourly measurements (UTC) of ozone (ppbv), nitric oxide (ppbv), nitrogen dioxide (ppbv), carbon monoxide (ppmv), and PM2.5 (microgram per cubic meter), from 1 January 2014 to 1 June 2020.