Powell is a city in Delaware County, Ohio, United States. The population was 6,247 at the 2000 census. The community was first settled around 1801, two years before Ohio became a state. It was named "Middlebury" at the time, because the first settlers came from the Middlebury, Connecticut area. In 1857, Judge Thomas Powell established the first post office in the community, and the residents decided to adopt his name. Powell was finally incorporated as a municipality in 1947.