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Area Code 628 Explained

State California
Timezone Pacific
Is Area Code 628 Toll Free? No

Each geographic area in the US is assigned an area code that accompanies every telephone phone number in use in America.

Where Is Area Code 628?

The 628 area code serves the San Francisco, Marin County and parts of Mill Valley, San Anselmo, San Rafael, Larkspur, Belvedere, Brisbane, Fairfax, Sausalito, Novato and San Mateo county regions. This area code was first introduced in February 2015 and operates within the pacific time zone.

Marin County is located just across the Golden Gate Bridge from San Francisco.

The 628 area code is an overlay for 415, overlays are why some areas have two area codes. The 415 area code is one of the first three area codes implemented in the state of California and dates back to 1947. When overlays are introduced there is often a grace period for all calls, including local calls, to begin using the full ten-digit number (11 digits when if calling internationally and a country code is needed). This grace period allows customers to update fax machines, security systems, tablets, cell phones and landlines to the new protocol.

Calls to 628 numbers can be made by first adding the three digit Numbering Plan Area (NPA) Code followed a seven-digit number made up of the central office code (NXX) and the subscriber number.

How new area codes are introduced

The use of area codes to accompany telephone numbers began in the 1940s. The idea and design was created by the North American Numbering Plan (NANP) and  AT&T. It was envisioned as a toll network that could encompass up to 152 area codes in total. The area codes were applied to geographic areas in both the US and Canada. Each area code could support up to 540 central offices and almost eight million unique seven-digit telephone numbers.

New area codes generally become necessary when the population of an area increases beyond the capacity of the existing area codes. When the limit is approaching, a split or overlay will occur to increase the volume of potential phone numbers. In California, new area codes area generally approved by the California Public Utilities Commission (CPUC).

Today, original area codes such as New York’s 212 have been overlaid with additional, newer area codes. Economic development spurs the need for additional area codes as older ones are exhausted. Once it is determined that a new area code is needed, how and when it will be introduced is decided in the US at the state level.

Scams associated with the 628 area code

As with many area codes in California, the 628 area code is associated with numerous telephone scams. People receiving these calls have reported many scams on the internet. These include auto warranty scams, dating scams and auto insurance scams. Some people have also received calls related to a puppy scam, as well as a loan forgiveness fraud. Perpetrators have pretended to be from UPS and Medicare in order to extract money from those who answer.

If you receive a telephone call and you do not recognize the number, hesitate to answer it. Calls that are important will be registered if you have enough space on your phone to receive messages. Anyone with actual important information will leave a message and provide you with a call back number. Some scam artists do this too, however. Because of this, it is prudent to be on the lookout for something that sounds like it might not be genuine.

When in doubt, contact the company or department that says they are calling you, directly. If the caller says they are reaching you from Visa, for example, hang up and contact Visa at their official number. You will find out if the call you received is truly legitimate.

As a rule of thumb, it is best practice to never supply your bank account, credit card, or other personal information to anyone over the phone.



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