Stonington, CT has a population of 973 and is the 15,331st largest city in the United States. The population density is 2,853 per sq mi which is 340% higher than the Connecticut average and 3049% higher than the national average. The median age in Stonington is 57 which is approximately 39% higher than the Connecticut average of 41. In Stonington, 52% of the population over 15 years of age are married, 97% speak English and 1% speak Spanish. 29% of Stonington residents were born in Connecticut, 65% were born out of state, 2% were born outside of the United States and 4% were foreign born.