Denison, TX has a population of 23,080 and is the 1,891st largest city in the United States. The population density is 807 per sq mi which is 732% higher than the Texas average and 791% higher than the national average. The median age in Denison is 40 which is approximately 16% higher than the Texas average of 34. In Denison, 57% of the population over 15 years of age are married, 92% speak English and 7% speak Spanish. 70% of Denison residents were born in Texas, 25% were born out of state, 1% were born outside of the United States and 4% were foreign born.