Rockford, ID has a population of 345 and is the 21,691st largest city in the United States. The population density is 311 per sq mi which is 1529% higher than the Idaho average and 243% higher than the national average. The median age in Rockford is 25 which is approximately 31% lower than the Idaho average of 36. In Rockford, 70% of the population over 15 years of age are married, 80% speak English and 20% speak Spanish. 74% of Rockford residents were born in Idaho, 13% were born out of state, 0% were born outside of the United States and 13% were foreign born.