Lockport, IL has a population of 25,096 and is the 1,721st largest city in the United States. The population density is 2,193 per sq mi which is 887% higher than the Illinois average and 2321% higher than the national average. The median age in Lockport is 36 which is approximately 4% lower than the Illinois average of 37. In Lockport, 61% of the population over 15 years of age are married, 91% speak English and 2% speak Spanish. 86% of Lockport residents were born in Illinois, 8% were born out of state, 0% were born outside of the United States and 5% were foreign born.