As of August, 415 is no longer Marin’s only numerical telephone prefix — 628 has joined the game in an area code overlay, meaning there will be two different area codes in the region from here on out. Practice starting your local calls with 1+415 when phoning your preexisting 415 contacts, as beginning in February 2015 calls made with only seven digits will not be completed. Existing phone numbers won’t change, but all new numbers issued in Marin and San Francisco counties will receive the new area code.
Area Code Overlay
