Bannock County is a county located in the southeastern part of the U.S. state of Idaho. As of the 2010 Census the population was 82,839, making it the fifth-most populous county in Idaho. The county seat and largest city is Pocatello. Bannock County borders Bingham County to the north, Caribou County to the east, Franklin County to the east and south, Oneida County to the west, and Power County to the west. The county was established in 1893 and named after the local Bannock tribe.
Bannock County comprises the Pocatello, ID Metropolitan Statistical Area.