The 304 area code is notable for its coverage of the entire state of West Virginia, playing a significant role in the state's telecommunications landscape.

Statewide Coverage and Historical Significance: The 304 area code was established in 1947 as part of the original North American Numbering Plan. It is unique in that it serves the entire state of West Virginia, making it one of the few remaining area codes in the United States that covers an entire state. This statewide coverage has remained unchanged since its inception, simplifying telecommunications across West Virginia.

Introduction of Overlay Area Code: To address the increasing demand for phone numbers, an overlay area code, 681, was introduced to the entire state of West Virginia in 2009. This overlay ensures a continuous supply of phone numbers while allowing existing 304 number holders to retain their numbers. The introduction of the 681 area code marked a significant milestone in West Virginia's telecommunications history.

Ten-Digit Dialing Requirement: With the introduction of the 681 overlay, ten-digit dialing (area code + phone number) became mandatory for all local calls within West Virginia. This change necessitated a shift in dialing practices for residents and businesses across the state, reflecting the evolving landscape of communication technology and the need for adaptability in numbering resources.

These key facts about the 304 area code highlight its role in providing comprehensive telecommunication services across West Virginia. Its implementation facilitates efficient and unified communication within the state, supporting a wide range of economic, cultural, and social activities.