Florida currently utilizes 17 area codes. When first established by AT&T and the Bell System in 1947, 305 covered the entire state of Florida. The most recently added was 239 in 2002. Today, 305 is the most populated with an estimated 2.1 million of the state's 18.8 million residents.
Sources: North American Numbering Plan Administration (NANPA), telecom providers, and the U.S. Census Bureau.