Reported (520) XXX-XXXX phone numbers lookup

Area Code 520 History and Coverage

Area code 520 was created in 1995 through geographical separation of the initial 602 numbering plan territory of Arizona. This being an area code created since the North American Numbering Plan of 1947 which had assigned only one area code 602 to Arizona, its creation has been a big departure from the previous state. Initially, area code 520 had a much bigger territory than today.

928 was separated from 520 in 2001 and the state's northwestern regions became covered by the new code. The separation brought about changes whereby areas including the Colorado Plateau, parts of the Mogollon Rim region and Colorado River were covered by area code 928. Thus, this separation marked the establishment of boundaries which have continued to govern area code 520 since then.

Arizona's regions needed more number plan capacity separately as the population continued to increase. In the remaining territory, the physical environment is characterized by basin-and-range terrain, ranging from desert valleys to upland regions close to the state line of New Mexico. Roadways like the Interstate 10 and Interstate 19 traverse through parts of this area linking the interior desert region to the border region. Huachuca Mountains and adjacent valleys form the southern eastern regions of this area code after 2001.