Oklahoma Area Code Information
(918 and 539)
Oklahoma is currently using four area codes. Oklahoma has had two area code splits and is utilizing one area code overlay. This new area code overlay was implemented on April 1, 2011 at which time area code 539 was put into service to provide numbering relief in area code 918.
Area code 405 originally covered all of Oklahoma when it was established in 1947. It was not until 1953 that Oklahoma experienced sufficient growth in population and telephone use to need an additional area code. It was at that time that area code 405 was split to form area code 918. In 1997 area code 405 was split again to form area code 580.
Today area code 405 covers central Oklahoma including Oklahoma City. Area codes 918 and 539 covers northeastern Oklahoma including Tulsa and area code 580 covers the southern and western portions of Oklahoma.
Changes and History of Oklahoma Area Codes:
Area code 405 was put into service. Area code 405 has been split two times. In 1953 area code 405 was split to form area code 918. In 1997 area code 405 was split to form area code 580.
Area code 918 was put into service. Area code 918 was created from a split of area code 405.
Area code 580 was put into service. Area code 580 was created from a split of area code 405.
Area code 539 was put into service as an overlay of area code 918.