Burlington, IA has a population of 25,492 and is the 1,688th largest city in the United States. The population density is 1,763 per sq mi which is 3128% higher than the Iowa average and 1846% higher than the national average. The median age in Burlington is 41 which is approximately 7% higher than the Iowa average of 38. In Burlington, 54% of the population over 15 years of age are married, 97% speak English and 2% speak Spanish. 70% of Burlington residents were born in Iowa, 28% were born out of state, 0% were born outside of the United States and 2% were foreign born.