In the first part of this series, we discussed the creation of area codes. The North American Numbering Plan (NANP), completed in 1947, was implemented gradually. The plan’s governing body, known as NANPA, gave the first area code, 201, to New Jersey. On November 10, 1951, the mayor of Englewood, New Jersey made the first direct-dialed long-distance call to the mayor of Alameda, California. The system was nationwide by the early 1960s. In the late 1980s, NANPA began requiring all long-distance calls to be prefaced with 1-, so that local prefixes with the second digit of 0 or 1 could be used.

Since 1990, a confluence of events has caused a rapid expansion of area codes in the U.S. and Canada (NANP also includes U.S. territories and some Caribbean countries). First was the explosion of new technology requiring phone numbers, such as the fax, modem, and cellular phone. Second was the deregulation of the telecommunications industry.

Area codes are created in one of two ways: a split or an overlay. A split divides an area into smaller regions, one of which retains the old area code while the others receive a new code. In an overlay, multiple area codes are assigned to the same geographic region. Beginning in 1995, NANPA allow the digits 2 through 8 to be used as the second digit of area codes, reserving 9 for future expansion. Area code 334 in Alabama and 360 in Washington were the first area codes not to have a 0 or 1 as the second digit.

Today, the area code system is administered by Neustar, an independent, nongovernmental organization under contract with the Federal Communications Commission (FCC). With the continued innovation of communication technology, such as VOIP (Voice Over Internet Protocol) and Google Voice and similar services, the demand for new phone numbers will only increase exponentially. One study estimates that NANPA will run out of useable 10-digit telephone numbers by 2038. At that point, it may become necessary to move to an 11- or 12-digit system.

The explosion in cell phone usage and number portability means that area codes are no longer tied to a geographic area; you can move from Maine to Oregon to Oklahoma and keep the same phone number. (The United States is one of the few countries that does not have a designated area code for cell phones. One was assigned in New York, but the FCC struck down the use of service-specific area codes.) It also means that some area codes maintain a certain cachet; 212, for example, is a coveted Manhattan area code.

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