St. Charles is a city in Madison County, Iowa, United States.

[7] According to the United States Census Bureau, the city has a total area of 0.54 square miles (1.40 km2), all of it land.

There were 274 housing units at an average density of 441.1 per square mile (170.3/km2).

As of the 2010 United States Census,[11] there were 653 people, 258 households, and 184 families living in the city.

There were 270 housing units at an average density of 500.0 per square mile (193.1/km2).

The racial makeup of the city was 97.1% white, 1.7% African American and 1.2% from two or more races.

23.3% of all households were made up of individuals, and 10.5% had someone living alone who was 65 years of age or older.

As of the 2000 United States Census,[12] there were 619 people, 246 households, and 171 families living in the city.

There were 253 housing units at an average density of 450.3 per square mile (173.9/km2).

26.4% of all households were made up of individuals, and 11.8% had someone living alone who was 65 years of age or older.