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WUTC orders telephone companies to share prefixes in area code 360

The telecommunications industry's plan to add a new prefix in western Washington is on indefinite hold by the Washington Utilities and Transportation Commission.

In June 2003 the national number administrator released these projections for when area codes in Washington state would run out of prefixes:

Area Code
(4th quarter)
(1st quarter)
(3rd quarter)
(1st quarter)
(1st quarter)

Instead of adding a new area code as requested, the WUTC and federal regulators have required telecommunications companies to use the existing supply of telephone prefixes more efficiently through "number pooling."

Number pooling allows up to 10 companies to share a single telephone prefix. Each company is assigned a block of 1,000 numbers within the prefix, which has a total of 10,000 numbers available. Without number pooling, each company has to use a separate prefix in each area where it offers service, even if it has only a few customers. This inefficient allocation of prefixes has been the main cause of the exhaustion of telephone area codes.

The number pooling order follows on the WUTC's decision in August 2001 to delay for at least a year the planned overlay of a new area code in western Washington.

The new 564 area code was planned to overlap Western Washington's four existing area codes. As an overlay, the new area code would require all customers to dial 10 digits to complete a local. Currently, Western Washington customers have an option to use 7 or 10 digits when making a local call. (Customers can even use 11 digits -- 1 plus the area code and phone number -- to dial local calls.)

Rather than set another date for introducing the new area code, the WUTC directed its staff to monitor number use on a monthly basis and determine in 2002 whether to propose a new date for the start of the area code. Since 2001 the WUTC has closely monitored the use of prefixes and continues to see no need for an additional area code.

Before the commission acted in August 2001, the area code and mandatory 10-digit dialing were to go into effect Oct. 20, 2001. The commission indicated 10-digit dialing could be delayed for longer than a year--or avoided altogether. Staff said that new software that will be installed in the telephone network in the near future has the potential of allowing phone numbers to be shared more efficiently than currently.

"We don't want to go to 10-digit dialing any sooner than we have to," said Chairwoman Marilyn Showalter. "In our judgment, consumers would rather delay mandatory 10-digit dialing than keep to a previously set date that is now earlier than necessary--and may never be necessary.''

The commission based its decision on a recommendation by its staff that the current deadline of Oct. 20, 2001 be extended until at least the fall of 2002 before implementing the new 564 area code and mandatory 10-digit local calling for telephone customers in western Washington. Staff members believe there are enough telephone prefixes in the existing area codes (360, 206, 425, and 253) to meet the telephone industry's needs for the next year.

Telephone companies have become more efficient in how they use telephone numbers, and the entry of new telephone companies that occurred in the late 1990s has virtually stopped. As a result, the WUTC staff expects that during 2001 more telephone prefixes to be returned by telephone companies than will be issued to telephone companies.

Staff contact: Wilford Saunders
Posted/updated: 05/14/2007
Document list:
991627   Documents   Schedule   Orders   All
991535   Documents   Schedule   Orders   All


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