Area code 975

Area Code 816 is the area code for most of northwestern Missouri. It includes the Kansas City metropolitan area, and the city of St. Joseph to the north. This area code originally covered most of the northern third of Missouri, including its borders with Iowa, Kansas, and Nebraska, but has been reduced so that it only borders Kansas. Within Missouri, 816 borders only area code 660, the latter being a relief code when 816 was nearing exhaustion.

When the North American Numbering Plan was created in 1947, Missouri was divided into two numbering plan areas (NPAs). Area code 816 served all points west of Jefferson City, while area code 314 served the east, including St. Louis. However, in 1951 a third NPA, area code 417, was created for the southwest, including the cities of Branson, Joplin, and Springfield.

By late 1996 the proliferation of cell phones, especially in the Kansas City area, and other market reforms related to deregulation by the Telecommunications Act of 1996, required that northwestern Missouri received an additional area code. The supply of telephone numbers was further limited because the Kansas City LATA extends some distance into eastern Kansas, meaning that several numbers in area code 913, the area code for most of the Kansas side of the Kansas City area, were not available for use.

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