Wentzville is a city and suburb located in western St. Charles County, Missouri, in the United States. It is situated within the metropolitan area of St. Louis.
As of the 2024 U.S. Census Bureau estimates, Wentzville has a population of 48,646, ranking it as the 15th-largest city in Missouri. The city was noted for being Missouri's fastest-growing city by percentage increase during the period from 2000 to 2020.