We used both adult and larval survey techniques during the summers of 2016 and 2017 to determine the mosquito species present in 36 counties of southern and western Missouri. The study included adult traps such as Omni-Directional Fay–Prince traps and Centers for Disease Control and Prevention traps baited with dry ice and octanol. Field-workers took larvae and pupae from standing water in artificial containers and returned them to the laboratory and placed them in emergence cages. When the mosquitoes emerged, we identified them as adults along with the contents of the adult traps. We sorted over 35,000 mosquitoes by sex, and then identified the females to species. The survey identified 8 genera and 40 species. This article reports the counties in which we collected each species.