Avoca, IA has a population of 1,478 and is the 12,778th largest city in the United States. The population density is 620 per sq mi which is 1036% higher than the Iowa average and 585% higher than the national average. The median age in Avoca is 38 which is approximately 1% lower than the Iowa average of 38. In Avoca, 68% of the population over 15 years of age are married, 100% speak English and 0% speak Spanish. 67% of Avoca residents were born in Iowa, 33% were born out of state, 0% were born outside of the United States and 0% were foreign born.