Flatonia, TX has a population of 1,488 and is the 12,739th largest city in the United States. The population density is 919 per sq mi which is 713% higher than the Texas average and 914% higher than the national average. The median age in Flatonia is 40 which is approximately 17% higher than the Texas average of 34. In Flatonia, 50% of the population over 15 years of age are married, 45% speak English and 52% speak Spanish. 65% of Flatonia residents were born in Texas, 8% were born out of state, 0% were born outside of the United States and 27% were foreign born.