The original configuration of the nationwide telephone numbering plan of 1947 divided the state of Texas into four numbering plan areas (NPAs) with the following area codes: 214, 512, 713, and 915. The northwestern part, stretching from the far west El Paso to the Texas Panhandle in the north and to Fort Worth in the east, was identified with area code 915, while area code 214 was assigned to the northeastern part of the state, roughly from a line just west of DallastoWaco, to the borders of Arkansas and Louisiana.
In 1954, most of Tarrant County was combined with much of the eastern region of area code 915 to form area code 817.
Despite the growth of the Dallas metropolitan area in the second half of the 20th century, this configuration remained in place for thirty six years. In 1990, the entire eastern portion of the 214 area was split off with area code 903.
The 1990 split was intended as a long-term solution, but within five years 214 was close to exhaustion due to the rapid growth of the Metroplex as well as the popularity of cell phones, fax machines and pagers. As a remedy, all of the old 214 territory outside Dallas and Dallas County was split off with area code 972 in 1996. Within only two years, however, both 214 and 972 were on the verge of exhaustion again. Area code 469 was introduced on July 1, 1999, in an overlay plan for most of the eastern portion of the Metroplex. At the same time, the 214/972 boundary was "erased," and 972 was converted into an additional overlay for the entire region. The result was three area codes overlaying the same area, with ten-digit dialing required for all calls.
While this had the effect of allocating over 23 million numbers to an area of just over nine million people, under 2018 projections, the Dallas area would need a fourth area code by mid-2021.[1] Area code 945 was selected as the fourth area code in the Dallas overlay, after receiving approval from the Public Utility Commission of Texas.[2] Central office code assignments for NPA 945 have been available since January 15, 2021,[3] but can only be requested after all existing area codes are exhausted.[4] Current projections suggest that a fifth area code will not be needed until around 2032.[5]
