New Liberty, IA has a population of 166 and is the 25,250th largest city in the United States. The population density is 1,839 per sq mi which is 3267% higher than the Iowa average and 1930% higher than the national average. The median age in New Liberty is 37 which is approximately 3% lower than the Iowa average of 38. In New Liberty, 76% of the population over 15 years of age are married, 97% speak English and 3% speak Spanish. 84% of New Liberty residents were born in Iowa, 14% were born out of state, 0% were born outside of the United States and 2% were foreign born.