St. Charles County, Missouri

county in Missouri, United States

St. Charles County is a county in Missouri, United States. The county seat is St. Charles. In 2020, 405,262 people lived there,[1] making it the third-most populous county in Missouri.

St. Charles County in Missouri
The flag of St. Charles County, Missouri

St. Charles County is part of the St. Louis, MO-IL Metropolitan Statistical Area and has many of the city's northwestern suburbs.


  1. "QuickFacts: St. Charles County, Missouri". United States Census Bureau. Retrieved August 11, 2023.