South Miami, FL has a population of 12,207 and is the 3,370th largest city in the United States. The population density is 5,387 per sq mi which is 1735% higher than the Florida average and 5846% higher than the national average. The median age in South Miami is 39 which is approximately 6% lower than the Florida average of 42. In South Miami, 46% of the population over 15 years of age are married, 49% speak English and 44% speak Spanish. 42% of South Miami residents were born in Florida, 23% were born out of state, 2% were born outside of the United States and 34% were foreign born.