Port St. Joe, FL has a population of 3,424 and is the 8,155th largest city in the United States. The population density is 362 per sq mi which is 23% higher than the Florida average and 300% higher than the national average. The median age in Port St. Joe is 45 which is approximately 9% higher than the Florida average of 42. In Port St. Joe, 53% of the population over 15 years of age are married, 97% speak English and 1% speak Spanish. 67% of Port St. Joe residents were born in Florida, 31% were born out of state, 0% were born outside of the United States and 2% were foreign born.