Harrington is a city in Kent County, Delaware, United States. It is part of the Dover metropolitan statistical area. Harrington hosts the annual Delaware State Fair each July. The population was 3,774 in 2020.

Kent County is a county located in the central part of the U.S. state of Delaware. As of the 2020 census, the population was 181,851, making it the least populous county in Delaware. The county seat is Dover, the state capital of Delaware. It is named for Kent, an English county.