Garwin, IA has a population of 503 and is the 19,494th largest city in the United States. The population density is 500 per sq mi which is 815% higher than the Iowa average and 452% higher than the national average. The median age in Garwin is 44 which is approximately 16% higher than the Iowa average of 38. In Garwin, 55% of the population over 15 years of age are married, 97% speak English and 2% speak Spanish. 85% of Garwin residents were born in Iowa, 14% were born out of state, 0% were born outside of the United States and 0% were foreign born.