Area code 415 is a North American telephone area code assigned to San Francisco and Marin County, California. First assigned in 1947 as one of the original 86 area codes in the North American Numbering Plan, 415 is among the oldest and most recognized area codes in the country. It serves the city of San Francisco, all of Marin County, and a small part of San Mateo County, and is a local (non-toll-free) area code in the Pacific Time Zone.