Geronimo, TX has a population of 1,124 and is the 14,432nd largest city in the United States. The population density is 138 per sq mi which is 42% higher than the Texas average and 52% higher than the national average. The median age in Geronimo is 40 which is approximately 18% higher than the Texas average of 34. In Geronimo, 51% of the population over 15 years of age are married, 56% speak English and 43% speak Spanish. 78% of Geronimo residents were born in Texas, 11% were born out of state, 0% were born outside of the United States and 11% were foreign born.