Thompsonville, CT has a population of 8,873 and is the 4,321st largest city in the United States. The population density is 4,360 per sq mi which is 492% higher than the Connecticut average and 4712% higher than the national average. The median age in Thompsonville is 36 which is approximately 11% lower than the Connecticut average of 41. In Thompsonville, 37% of the population over 15 years of age are married, 76% speak English and 14% speak Spanish. 51% of Thompsonville residents were born in Connecticut, 32% were born out of state, 2% were born outside of the United States and 15% were foreign born.