318 Area Code – Shreveport, Louisiana: Location, Time Zone & History

Telephone numbering in northern Louisiana has been rewritten several times since 1957, when 318 was carved out of the original 504 numbering plan area in a geographic split that gave nearly the entire western half of the state its own code. For over four decades 318 covered both northern and southern Louisiana, until the southern portion split away in 1999 to become area code 337, with permissive dialing starting that October and mandatory dialing following in March 2000.

Growth in phone number demand eventually caught up with the reduced territory as well. The Louisiana Public Service Commission approved an all-services overlay, area code 457, in May 2023 to relieve pressure without another boundary redraw. Permissive 10-digit dialing began February 24, 2025, became mandatory that August, and the first 457 numbers were issued starting September 25, 2025 -- a shift toward overlays rather than splits as the region's preferred way of adding capacity.

The numbering plan area today reaches Shreveport, Monroe, Alexandria, Bossier City, Ruston and Natchitoches, an economic base built on oil and gas extraction, agriculture and timber, the military presence at Barksdale Air Force Base, healthcare and higher education.