Mystic, CT has a population of 4,241 and is the 7,175th largest city in the United States. The population density is 1,265 per sq mi which is 95% higher than the Connecticut average and 1296% higher than the national average. The median age in Mystic is 56 which is approximately 39% higher than the Connecticut average of 41. In Mystic, 65% of the population over 15 years of age are married, 94% speak English and 2% speak Spanish. 37% of Mystic residents were born in Connecticut, 57% were born out of state, 2% were born outside of the United States and 5% were foreign born.