Mount Sterling, IL has a population of 2,184 and is the 10,515th largest city in the United States. The population density is 1,971 per sq mi which is 786% higher than the Illinois average and 2075% higher than the national average. The median age in Mount Sterling is 34 which is approximately 9% lower than the Illinois average of 37. In Mount Sterling, 54% of the population over 15 years of age are married, 99% speak English and 1% speak Spanish. 88% of Mount Sterling residents were born in Illinois, 10% were born out of state, 0% were born outside of the United States and 1% were foreign born.