ETSB&OA is divided into three areas based on county.
Upper Area:
Carter, Claiborne, Cocke, Graingers, Greene, Hamblen, Hawkins, Hancock, Jefferson, Johnson, Sullivan, Unicoi, and Washington counties.
Middle Area:
Anderson, Blount, Campbell, Knox, Morgan, Scott, Sevier, and Union counties.
Lower Area:
Bledsoe, Bradley, Cumberland, Fentress, Grundy, Hamilton, Loudon, McMinn, Marion, Meigs, Monroe, Polk, Rhea, Roane, and Sequatchie counties.