Decatur is a town in Meigs County, Tennessee, United States. The population was 1,395 at the 2000 census. It is the county seat of Meigs County.
The local pronunciation of the name is duh▪KAY▪ter (IPA: /dəkeɪtər/).
Decatur is located at 35°31′8″N 84°47′36″W / 35.51889°N 84.79333°W / 35.51889; -84.79333 (35.518871, -84.793201). The town is situated at the western base of No Pone Ridge, an elongate ridge characteristic of the Appalachian Ridge-and-Valley Province. Just west of Decatur, the Tennessee River flows around a blunt peninsula known as Armstrong Bend. This section of the river is technically part of the river's Chickamauga Lake impoundment.