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Area Code Conservation

Over the past several years, the PUC has instituted several numbering conservation efforts to slow the proliferation of area codes in Pennsylvania. These efforts have resulted in conserving over millions of telephone numbers throughout the state.

Thousands-Block Pooling

The Federal Communications Commission (FCC) has given the PUC authority to implement mandatory thousands-block number pooling in all of Pennsylvania's area codes. All area codes have mandatory pooling implemented.

Number pooling requires participating telephone companies to return unused telephone numbers in blocks of 1,000. The numbers then are given to other phone companies that need them.

Pennsylvania Pooling History

The Federal Communications Commission (FCC) in May 1999, established a plan for a national rollout of thousands-block pooling on March 15, 2002. The FCC had granted states interim authority to implement thousands-block pooling trials. Pennsylvania's first thousands-block pooling trial began in the 610/484 area on April 27, 2001. In accordance to the FCC's national pooling schedule, the pooling for 215/267 began in August 2002.

As part of the trial, phone companies returned unused blocks of 1,000 numbers. The numbers are then reassigned to other companies that need phone numbers.

The pooling trials did not have any immediate impact on consumers and proved to use the present area codes more efficiently while ultimately delaying the need to add new area codes in the future. It has also delayed the need to use numbers from the new 835 area code which has been suspended as of May 2001.

The FCC allowed Pennsylvania to implement a trial in both 412 and 610 but could do only one at a time.

After reviewing comments from consumers, the telecommunications industry and other parties, the PUC chose to begin the pooling trial in the 610 area code. There are more numbers immediately available for pooling in the 610/484 area than in the 412 (Pittsburgh) area. After the first trial was implemented the PUC started the second one.

On May 18, 2010, the FCC granted delegated authority to implement further Mandatory Pooling than previously granted in the 215/267, 570, 610/484, 717, and 814 NPAs. In an order on June 3, 2010, Pennsylvania implemented this delegated authority.

NXX Code Reclamation

The FCC, as part of its efforts to conserve numbers, gave state commissions the authority to reclaim NXX codes that have not been assigned to customers in six months. NXX codes are the first three digits of a phone number following the area code. Each one contains approximately 10,000 phone numbers.

By reclaiming the unused telephone numbers in blocks of 10,000 numbers, the PUC is able to return the blocks to the North American Numbering Plan Administrator (NANPA), which then can reassign the numbers to another telephone company, ensuring the more efficient use of numbers. The NANPA is the FCC unit responsible for distributing area codes.

This reclamation effort also includes the 1,000 block pooling numbers that are not assigned to customers in six months.

Since February 2001, over 1 million telephone numbers have been reclaimed through companies returning NXX codes to NANPA.

Unavailable Phone Numbers

There were almost 1.5 million telephone numbers designated as "permanently" unavailable to customers in eight of Pennsylvania’s area codes. By working with telephone carriers, in August 2003 the PUC was able to release 65 NXX codes, or 650,000 telephone numbers, that otherwise would have remained unavailable to customers.

Some NXX codes are designated by the FCC and the telecommunications industry as permanently unavailable because they are used for such purposes as network testing, public safety (911), directory assistance (555) and telecommunications relay services (711). In some cases numbers had been traditionally unassigned to customers to avoid dialing confusion, or for technical reasons.

In addition, other NXX codes that match the area code are never released, such as (717) 717-0000. Due to expanding area codes, NXX codes that match a neighboring area code may also be unavailable. For example Philadelphia has three area codes: 215, 267 and 445. There are no telephone numbers such as (215) 267-0000 or (267) 215-0000 pr (445) 215-0000.

Some telephone numbers were deemed unavailable for no apparent reason. These are the numbers that the PUC asked to be returned to NANPA, so that they can be reassigned to another carrier.


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