Gilbert, IA has a population of 1,183 and is the 14,121st largest city in the United States. The population density is 1,204 per sq mi which is 2103% higher than the Iowa average and 1229% higher than the national average. The median age in Gilbert is 34 which is approximately 11% lower than the Iowa average of 38. In Gilbert, 68% of the population over 15 years of age are married, 99% speak English and 0% speak Spanish. 80% of Gilbert residents were born in Iowa, 19% were born out of state, 0% were born outside of the United States and 2% were foreign born.