Area code 704 was one of the original 86 area codes established in 1947 by AT&T and the Bell System, initially serving the entire state of North Carolina. This reflected the lower population density and limited telephone infrastructure of the mid-20th century. As the state's population grew, particularly around major urban centers, the need for more phone numbers led to changes in the area code's coverage.

In 1954, area code 704 was first split, creating the 919 area code for the eastern half of the state. Later, in 1998, the 704 area code was split again, with the new 828 area code serving the mountainous western region of North Carolina. This left 704 covering the Charlotte metropolitan area and its surrounding south-central counties. Today, the 704 area code remains closely associated with Charlotte, the state's largest city, and serves its metropolitan area along with several neighboring counties, now alongside its 980 overlay introduced in 2001.