Mounds, IL has a population of 1,054 and is the 14,821st largest city in the United States. The population density is 873 per sq mi which is 293% higher than the Illinois average and 864% higher than the national average. The median age in Mounds is 32 which is approximately 14% lower than the Illinois average of 37. In Mounds, 44% of the population over 15 years of age are married, 95% speak English and 2% speak Spanish. 70% of Mounds residents were born in Illinois, 25% were born out of state, 0% were born outside of the United States and 4% were foreign born.