Part of the East Welega Zone, Jimma Horo was bordered on the south by the East Shewa Zone, on the southwest by Bila Seyo, on the west by Abe Dongoro, on the northwest by Amuru Jarte, on the northeast by Abay Chomen, on the east by Guduru, and on the southeast by Jimma Rare.
Jimma Horo was a region within the East Welega Zone, delineated by borders: southward by the East Shewa Zone, southwestward by Bila Seyo, westward by Abe Dongoro, northwestward by Amuru Jarte, northeastward by Abay Chomen, eastward by Guduru, and southeastward by Jimma Rare.