We compare the community composition, abundance, and seasonality of mosquito species detected by the encephalitis virus surveillance (EVS) CO₂ traps and Centers for Disease Control and Prevention (CDC) light traps. Traps were run concurrently for a year during routine weekly monitoring in the vicinity of the city of Darwin in northern Australia. The EVS CO₂ traps detected far more individuals than CDC light traps notwithstanding a weaker suction fan, but species richness was similar. Regardless of variation in community composition among sites, differences between trap types were remarkably consistent. Seasonal trends in the abundance of 5 key species from each trap type were similar, but markedly more so in strongly seasonal species. Although EVS CO₂ traps outperformed CDC light traps for routine monitoring, the historical transition from the latter to the former is unlikely to have major consequences for the identification of community composition or detection of seasonal trends in key species.