About: List of counties in Oklahoma

This is a list of the seventy-seven counties in the U.S. state of Oklahoma. Oklahoma is ranked 20th size and 17th in the number of counties, between Mississippi with 82 counties and Arkansas with 75 counties. Oklahoma originally had seven counties when it was first organized as the Oklahoma Territory. These counties were designated numerically, first through seventh. New counties added after this were designated by letters of the alphabet. The first seven counties were later renamed.