what county is prosper in
Prosper, TX. Online Offers. Prosper is a town in Collin and Denton counties in the U.S. state of Texas. The population was 2,097 at the 2000 census. As of the census of 2000, there were 2,097 people, 678 households, and 589 families residing in the town. The latest 2009 census brought Prosper to a population of 9,350. The population density was 423.6 per square mile (163.6/km2).