Benton, IL has a population of 7,148 and is the 5,103rd largest city in the United States. The population density is 1,305 per sq mi which is 487% higher than the Illinois average and 1340% higher than the national average. The median age in Benton is 40 which is approximately 7% higher than the Illinois average of 37. In Benton, 56% of the population over 15 years of age are married, 97% speak English and 2% speak Spanish. 80% of Benton residents were born in Illinois, 19% were born out of state, 0% were born outside of the United States and 1% were foreign born.