St. Charles, MI has a population of 2,016 and is the 10,928th largest city in the United States. The population density is 953 per sq mi which is 445% higher than the Michigan average and 952% higher than the national average. The median age in St. Charles is 42 which is approximately 8% higher than the Michigan average of 39. In St. Charles, 60% of the population over 15 years of age are married, 99% speak English and 1% speak Spanish. 89% of St. Charles residents were born in Michigan, 11% were born out of state, 0% were born outside of the United States and 1% were foreign born.