Numbering plan areas and area codes of Texas with numbering plan area 430/903 highlighted.
Area codes 903 and 430 are telephonearea codes in theNorth American Numbering Plan (NANP) for the northeastern part of theU.S. state ofTexas, includingKilgore,Texarkana,Tyler, andSherman. The numbering plan area begins just north and east of theDallas–Fort Worth metroplex, and extends to the Oklahoma, Arkansas, and Louisiana state borders. Area code 903 was created November 4, 1990 in a split ofarea code 214. Area code 430 was assigned to the same service area on February 15, 2003 in creation of anoverlay. Before October 18, 1980, area code 903 was assigned to an area in northwestern Mexico.
From 1962 until October 18, 1980, area code 903 was an area code for parts of northwesternMexico served by Telefónica Fronteriza, which homed on AT&T lines in the United States rather than Telefonos de Mexico (Telmex). Telmex and the Mexican government forcibly acquired the TF exchanges, and in 1980, Telmex reorganized the area codes of the country, assigning 6 as the initial digit of 8-digit numbers in the northwest. At this point, 903 was withdrawn from use and replaced witharea code 706,[1] as one of two area codes for alternative dialing into certain parts of Mexico from the United States. The other area code used for this was905. 706 and 905 weredial-around codes that replaced +52(5) forMexico City and +52(6) for northwestern Mexico. In February 1991, 706 and 905 were withdrawn pending assignment within the NANP service area.
