Gallatin, TN has a population of 33,426 and is the 1,272nd largest city in the United States. The population density is 1,057 per sq mi which is 590% higher than the Tennessee average and 1066% higher than the national average. The median age in Gallatin is 37 which is approximately 3% lower than the Tennessee average of 39. In Gallatin, 56% of the population over 15 years of age are married, 91% speak English and 7% speak Spanish. 58% of Gallatin residents were born in Tennessee, 35% were born out of state, 1% were born outside of the United States and 6% were foreign born.