Arkansas currently utilizes 3 area codes. When first established by AT&T and the Bell System in 1947, 501 covered the entire state of Arkansas. The most recently added was 479 in 2002. Today, 870 is the most populated with an estimated 1.2 million of the state's 2.9 million residents.
Sources: North American Numbering Plan Administration (NANPA), telecom providers, and the U.S. Census Bureau.