County of Marin - Press Releases - Area Code Change

For Immediate Release
July 25, 2014

Marin Prepares for 628 Area Code

Effective in August, 415 users should add area code to all local calls

San Rafael, CA – The County of Marin would like to remind local residents that a new telephone area code – 628 – is being added to the area served by the existing 415 area code to accommodate demand for new phone numbers.

The 415 area code, which generally covers most of Marin, the County of San Francisco and a small portion of San Mateo County, will have to be included when 415 customers are calling within that area code starting in February 2015. The California Public Utilities Commission (CPUC) and the 415 Public Education Program Task Force is urging Marin residents to start using area codes when dialing all numbers beginning Aug. 16.

The change has been in the works since 1998, when the CPUC was first petitioned for the new 628 area code. Number conservation efforts extended the life of the existing 415 area code since then. Marin has been in the 415 area code since it was first established in 1947.

Here is more information about the change provided by the 415 Public Education Program Task Force.

What is an area code overlay?

An overlay is the addition of another area code to the same geographic region as an existing area code. An overlay does not require customers to change their existing area code.

What is the new dialing procedure?

To complete calls, the new procedure requires callers to dial 1 plus the area code plus a seven-digit number. Soon all calls in the 415 area code that are currently dialed with seven digits need to be dialed using 11 digits.

When will the change begin?

Effective Aug. 16, customers should begin using the new dialing procedure when placing local calls from the 415 area code. If customers forget and use the old dialing procedure of dialing just seven digits, calls will still complete until Feb. 21, 2015.

Beginning Feb. 21, 2015, callers must use the new dialing procedure for all calls. After that date, calls made with seven digits will not be completed and a recording will provide instruction to hang up and dial again. Between Aug. 16, 2014 and Feb. 21, 2015, callers should practice using the new procedure whenever calls are placed from the 415 area code.   

Beginning March 21, 2015, new telephone lines or services may be assigned numbers with the 628 area code.

What do business customers need to do?

In addition to changing dialing procedures,  all services, automatic dialing equipment, or other types of equipment that are programmed with a seven-digit number will need to be reprogrammed to use the new dialing procedures. Some examples are life-safety systems, PBXs, fax machines, Internet dial-up numbers, alarm and security systems, gates, speed dialers, call forwarding settings and voicemail services. Businesses are advised to add the area code to company stationery or advertising materials before Feb. 21, 2015.

What is the test number for the 628 area code?

A test number has been established to enable business customers to verify that their equipment can complete calls to the new area code.  The test number, (628) 628-1628, will be available beginning Dec. 21 and will be in operation through April 21, 2015.

What will remain the same?

  • Existing telephone numbers, including current area code
  • The price of a call, coverage area, or other rates and services
  • What is a local call now will remain a local call regardless of the number of digits dialed
  • Dialing 911 as well as 211, 311, 411, 511, 611, 711 and 811

Questions about the dialing procedure change should be directed to local service providers or the Consumer Affairs division of the California Utilities Commission at 1-800-649-7570. Visit the California Utilities Commission website to share comments or find more information.


Brent Ainsworth
Public Information Specialist
County Administrator's Office

3501 Civic Center Drive
Suite #325
San Rafael, CA 94903
(415) 473-3084
Email: Brent Ainsworth
County Administrator website