Jewett City is a borough in New London County, Connecticut, in the town of Griswold. The population was 3,487 at the 2010 census. The borough was named for Eliezer Jewett, who founded a settlement there in 1771.
According to the United States Census Bureau, the borough has a total area of 0.8 square miles (2.1 km2), of which 0.7 square miles (1.8 km2) is land and 0.04 square miles (0.10 km2), or 4.00%, is water.
As of the census of 2000, there were 3,053 people, 1,337 households, and 743 families residing in the borough. The population density was 4,213.9 people per square mile (1,637.2/km2). There were 1,464 housing units at an average density of 2,020.7/sq mi (785.1/km2). The racial makeup of the borough was 92.07% White, 2.46% African American, 0.88% Native American, 1.44% Asian, 0.07% Pacific Islander, 1.11% from other races, and 1.97% from two or more races. Hispanic or Latino of any race were 2.85% of the population.
There were 1,337 households, out of which 29.2% had children under the age of 18 living with them, 34.8% were married couples living together, 15.7% had a female householder with no husband present, and 44.4% were non-families. 34.2% of all households were made up of individuals, and 11.4% had someone living alone who was 65 years of age or older.