Indiana counties that in whole or in part use 812 and 930. Area codes 812 and 930 serve the southern third of the state of Indiana. The area codes cover Evansville and most of its suburbs, the northern suburbs of Louisville and the northwestern suburbs of Cincinnati.Other cities in the area code are Bedford, Bloomington, Columbus, Greensburg, Jasper, Princeton, Seymour, Terre Haute, and Vincennes.he main area code, 812, was one of the original area codes introduced in 1947.