Flower Mound, TX has a population of 69,966 and is the 523rd largest city in the United States. The population density is 1,669 per sq mi which is 1622% higher than the Texas average and 1742% higher than the national average. The median age in Flower Mound is 40 which is approximately 16% higher than the Texas average of 34. In Flower Mound, 69% of the population over 15 years of age are married, 84% speak English and 6% speak Spanish. 43% of Flower Mound residents were born in Texas, 43% were born out of state, 2% were born outside of the United States and 12% were foreign born.