Peoria, IL has a population of 115,990 and is the 241st largest city in the United States. The population density is 2,407 per sq mi which is 983% higher than the Illinois average and 2557% higher than the national average. The median age in Peoria is 34 which is approximately 9% lower than the Illinois average of 37. In Peoria, 47% of the population over 15 years of age are married, 89% speak English and 5% speak Spanish. 72% of Peoria residents were born in Illinois, 19% were born out of state, 1% were born outside of the United States and 8% were foreign born.