North Liberty, IA has a population of 16,984 and is the 2,525th largest city in the United States. The population density is 1,921 per sq mi which is 3417% higher than the Iowa average and 2020% higher than the national average. The median age in North Liberty is 30 which is approximately 22% lower than the Iowa average of 38. In North Liberty, 51% of the population over 15 years of age are married, 94% speak English and 4% speak Spanish. 66% of North Liberty residents were born in Iowa, 29% were born out of state, 2% were born outside of the United States and 4% were foreign born.