San Antonio, FL has a population of 1,129 and is the 14,401st largest city in the United States. The population density is 836 per sq mi which is 185% higher than the Florida average and 823% higher than the national average. The median age in San Antonio is 42 which is approximately equal to the Florida average of 42. In San Antonio, 55% of the population over 15 years of age are married, 92% speak English and 5% speak Spanish. 48% of San Antonio residents were born in Florida, 46% were born out of state, 1% were born outside of the United States and 6% were foreign born.