St. Leo, FL has a population of 1,172 and is the 14,171st largest city in the United States. The population density is 1,047 per sq mi which is 257% higher than the Florida average and 1056% higher than the national average. The median age in St. Leo is 19 which is approximately 54% lower than the Florida average of 42. In St. Leo, 4% of the population over 15 years of age are married, 88% speak English and 9% speak Spanish. 35% of St. Leo residents were born in Florida, 57% were born out of state, 2% were born outside of the United States and 6% were foreign born.