408/669 Area Code

[En Espaňol] 

On Oct. 20, 2011, the CPUC approved an all-services overlay that will add a new 669 area code to the same geographic region as the existing 408 area code in order to provide additional telephone numbers to meet increasing consumer demand. Beginning on April 21, 2012, customers having 408 telephone numbers may dial all 11 digits to place a call. After October 20, 2012, all calls will require dialing 1 plus the area code and the seven digit telephone number. Calls placed without the area code will result in a recording advising the caller to dial one plus the area code and the telephone number to complete a call.

An area code overlay adds a second area code to the same geographic region as an existing area code. Therefore, multiple area codes can co-exist within the same geographic region. New telephone numbers with the 669 area code will be issued to customers requesting new telecommunication services beginning in November 2012.

Customers will not be required to change their existing telephone numbers. But, consumers calling any number in the 408 area code will have to dial the area code plus phone number beginning six months from today. If they do not, their calls will still go through for a six-month grace period. The new dialing procedure must be used beginning one year from today.

The 408 area code is predominantly in Santa Clara County, as well as neighboring cities and small unincorporated portions of Alameda and Santa Cruz Counties. Cities in the 408 area code include San Jose (the state's third largest city), as well as the cities of Campbell, Cupertino, Gilroy, Los Gatos, Milpitas, Monte Sereno, Morgan Hill, Santa Clara, Saratoga, Sunnyvale, and a portion of Palo Alto.

New Dialing Procedure for Consumers with 408 Area Code 



The 408 area code, covering primarily Santa Clara County, is forecasted to require a new area code by the fourth quarter 2012. The new area code, 669, is necessary because all of the available three digit numbers combined with 408 are expected to be assigned by that date.

The 669 will be introduced in the form of an all services overlay. In anticipation of needing a new area code in October 2012, the CPUC, in conjunction with the North American Numbering Plan Administrator (NANPA), began the area code introduction process in December 2010. On December 2, 2010 the NANPA held meeting with affected service providers to get their input regarding the most appropriate method of introducing the 669. The industry consensus resulting from that meeting was to recommend an overlay. The CPUC held five meetings in March to inform the public and to receive public comment about the new area code alternatives and opened a web link to facilitate collecting maximum public comment. After the public meetings in March, the NANPA submitted an application to the CPUC for the new area code recommending the industry-desired solution.

In response to the NANPA’s application the CPUC opened a proceeding, considered the information presented by the NANPA and comments from the public and issued a proposed decision. The CPUC considered comments made by the public up until the decision is voted on.

The CPUC approved the overlay on October 20, 2011.

Service providers are required to implement the new area code with a specified period.

The CPUC has employed number conservation methods diligently since 2000. The conservation measures have postponed the need for a new area code significantly.

In evaluating whether a new area code is necessary, the public must be mindful that numbers are assigned to service providers in minimum blocks of 1000. A service provider may use the full 1000 numbers or only one number in that thousand block. In either case, the service provider may continue to hold the block for future use. Each block of 1000 numbers is a portion of a prefix assigned to a specific rate center. Once a prefix has been assigned to a rate center, blocks within that prefix may only be used to provide service to customers located within the geographic area served by that rate center.

A new area code may be necessary even though a large percentage of numbers within the area code are unassigned. This is because the need for a new code is determined by the availability of additional prefixes – three digit number combinations – for assignment within the area code. When the availability of additional three digit number combinations is diminishing, it is necessary to assign a new area code so that the supply of prefixes is replenished.

October 17, 2012: CPUC Reminds Consumers in 408 Area Code of Mandatory New Dialing Prodedure for Calls 

408 Public Meeting Materials including April 7, 2011 Meeting Report

408 Area Code History 

408 Prefix Assignments as of November 15, 2010

Service Providers Holding Blocks in the 408 area code

408 Number Assignments by Technology (graph)

Overlay Alternative #1 

Geographic Split Alternative #2 

Frequently Asked Questions 

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