Elmhurst, IL has a population of 45,742 and is the 897th largest city in the United States. The population density is 4,458 per sq mi which is 1905% higher than the Illinois average and 4820% higher than the national average. The median age in Elmhurst is 40 which is approximately 6% higher than the Illinois average of 37. In Elmhurst, 64% of the population over 15 years of age are married, 86% speak English and 5% speak Spanish. 74% of Elmhurst residents were born in Illinois, 17% were born out of state, 1% were born outside of the United States and 9% were foreign born.