Area codes 415 and 628 are

telephone A telephone is a telecommunications device that permits two or more users to conduct a conversation when they are too far apart to be easily heard directly. A telephone converts sound, typically and most efficiently the human voice, into e ...

area code A telephone numbering plan is a type of numbering scheme used in telecommunication to assign telephone numbers to subscriber telephones or other telephony endpoints. Telephone numbers are the addresses of participants in a telephone network, rea ...

s in the

North American Numbering Plan The North American Numbering Plan (NANP) is a telephone numbering plan for twenty-five regions in twenty countries, primarily in North America and the Caribbean. This group is historically known as World Zone 1 and has the international callin ...

(NANP) for the city of

San Francisco San Francisco (; Spanish language, Spanish for "Francis of Assisi, Saint Francis"), officially the City and County of San Francisco, is the commercial, financial, and cultural center of Northern California. The city proper is the List of Ca ...

and its northern suburbs in

Marin County Marin County is a county located in the northwestern part of the San Francisco Bay Area of the U.S. state of California. As of the 2020 census, the population was 262,231. Its county seat and largest city is San Rafael. Marin County is acros ...

(across the

Golden Gate The Golden Gate is a strait on the west coast of North America that connects San Francisco Bay to the Pacific Ocean. It is defined by the headlands of the San Francisco Peninsula and the Marin Peninsula, and, since 1937, has been spanned by th ...

), and the northeast corner of

San Mateo County San Mateo County ( ), officially the County of San Mateo, is a county located in the U.S. state of California. As of the 2020 census, the population was 764,442. Redwood City is the county seat, and the third most populated city following Daly ...

in the U.S. state of

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

. Area code 415 was one of the eighty-six

original North American area codes The original North American area codes were established by the American Telephone & Telegraph Company (AT&T) in 1947, following the demonstration of regional Operator Toll Dialing during the World War II period. The program had the goal of speedin ...

established in 1947, but modified in geographic configuration later. Area code 628 was assigned in 2015 to form an

overlay Overlay may refer to: Computers *Overlay network, a computer network which is built on top of another network *Hardware overlay, one type of video overlay that uses memory dedicated to the application *Another term for exec, replacing one process ...

in that numbering plan area in mitigation of central office prefix exhaustion.

History

When the North American Numbering Plan was installed by

AT&T AT&T Inc. is an American multinational telecommunications holding company headquartered at Whitacre Tower in Downtown Dallas, Texas. It is the world's largest telecommunications company by revenue and the third largest provider of mobile tel ...

for

Operator Toll Dialing Operator Toll Dialing was a telephone call routing and toll-switching system for the Bell System and the independent telephone companies in the United States and Canada that was developed in the 1940s. It automated the switching and billing of lo ...

in 1947, the state of

was divided into three numbering plan areas (NPAs) arranged as geographical zones in the southern part, the central part, and the northern part of the state. Area code 415 was assigned to central California, south of

area code 916 Area codes 916 and 279 are California telephone area codes that serve Sacramento, the state capital, and most of its suburbs. Area code 916 was one of the first three original area codes established in California in October 1947. It originally co ...

, and north of area code 213. It stretched from

Sacramento ) , image_map = Sacramento County California Incorporated and Unincorporated areas Sacramento Highlighted.svg , mapsize = 250x200px , map_caption = Location within Sacramento ...

in the north to

Bakersfield Bakersfield is a city in Kern County, California, United States. It is the county seat and largest city of Kern County. The city covers about near the southern end of the San Joaquin Valley and the Central Valley region. Bakersfield's populat ...

in the south. In 1950, the boundaries of the numbering plan area were redrawn to produce a division of the northern and central parts along a north-south-running dividing line. Numbering plan area 415 became the coastal region from the

North Coast North Coast or Northcoast may refer to : Antigua and Barbuda * Major Division of North Coast, a census division in Saint John Parish Australia *New South Wales North Coast, a region Canada *The British Columbia Coast, primarily the communiti ...

to the

Oregon Oregon () is a U.S. state, state in the Pacific Northwest region of the Western United States. The Columbia River delineates much of Oregon's northern boundary with Washington (state), Washington, while the Snake River delineates much of it ...

border, while 916 was redrawn to comprise the northeastern corner of the state. As part of this realignment, Sacramento was renumbered from area code 415 to 916, and Bakersfield to 213. With the preparations for nation-wide

direct distance dialing Direct distance dialing (DDD) is a telecommunication service feature in North America by which a caller may, without operator assistance, call any other user outside the local calling area. Direct dialing by subscribers typically requires extra d ...

(DDD) in the early 1950s,

area code 318 Area code 318 is a telephone area code in the North American Numbering Plan (NANP) for the northern and central parts of the U.S. state of Louisiana. The area code was created in 1957 in a split of Louisiana's original area code 504. Originally ...

was temporarily used in the San Francisco area, initially by customers in

Englewood, New Jersey Englewood is a city in Bergen County, in the U.S. state of New Jersey, which at the 2020 United States census had a population of 29,308. Englewood was incorporated as a city by an act of the New Jersey Legislature on March 17, 1899, from por ...

, participating in the first customer trials to reach the city, as well as some areas north of the

. In 1953, the entire Bay Area was "reunited" in using area code 415. Area code 415 has been split three times due to the Bay Area's rapid economic growth and demand for telecommunication services: * On March 1, 1959,

area code 707 Area code 707 is a telephone area code in the North American Numbering Plan (NANP) for the northwestern part of the U.S. state of California. It was created by a split of area code 415 on March 1, 1959. It serves part of the northern San Francis ...

was created from the northern part, and

area code 408 Area codes 408 and 669 are telephone area codes in the North American Numbering Plan (NANP) in the U.S. state of California. The numbering plan area comprises most of Santa Clara County and Northern Santa Cruz County, and includes Gilroy, Mo ...

was created for San Jose, the South Bay, the

Monterey Bay Monterey Bay is a bay of the Pacific Ocean located on the coast of the U.S. state of California, south of the San Francisco Bay Area and its major city at the south of the bay, San Jose. San Francisco itself is further north along the coast, by ...

, and the

Salinas Valley The Salinas Valley is one of the major valleys and most productive Agriculture, agricultural regions in California. It is located west of the San Joaquin Valley and south of San Francisco Bay and the Santa Clara Valley. The Salinas River (Califo ...

. (408 has since been split to

831 __NOTOC__ Year 831 ( DCCCXXXI) was a common year starting on Sunday (link will display the full calendar) of the Julian calendar. Events By place Byzantine Empire * Byzantine–Arab War: Emperor Theophilos invades the Abbasid dominion ...

and overlaid with 669.) * On September 2, 1991,

area code 510 Area is the quantity that expresses the extent of a region on the plane or on a curved surface. The area of a plane region or ''plane area'' refers to the area of a shape or planar lamina, while '' surface area'' refers to the area of an open s ...

was created for the

East Bay The East Bay is the eastern region of the San Francisco Bay Area and includes cities along the eastern shores of the San Francisco Bay and San Pablo Bay. The region has grown to include inland communities in Alameda and Contra Costa counties ...

, including

Oakland Oakland is the largest city and the county seat of Alameda County, California, United States. A major West Coast port, Oakland is the largest city in the East Bay region of the San Francisco Bay Area, the third largest city overall in the Bay A ...

. (510 has since been split to 925 and was overlaid by 341 in 2019.) * On August 2, 1997, area code 650 was created; the partition approximately followed the boundary between San Francisco, which (along with Marin County) kept 415, and

to the south, which received the new code. Deviations from the county line included a very small area east of the San Francisco Golf Club, which was changed to 650, and portions of

Brisbane Brisbane ( ) is the capital and most populous city of the states and territories of Australia, Australian state of Queensland, and the list of cities in Australia by population, third-most populous city in Australia and Oceania, with a populati ...

and

Daly City Daly City () is the second most populous city in San Mateo County, California, United States, with population of 104,901 according to the 2020 census. Located in the San Francisco Bay Area, and immediately south of San Francisco (sharing its ...

, which remained in 415. On February 21, 2015, the numbering plan area was transitioned to an

overlay plan Overlay may refer to: Computers *Overlay network, a computer network which is built on top of another network *Hardware overlay, one type of video overlay that uses memory dedicated to the application *Another term for exec, replacing one process ...

by adding area code 628 to the same service area for new numbers, making

ten-digit dialing Ten-digit dialing is a telephone dialing procedure in the countries and territories that are members of the North American Numbering Plan (NANP). It is the practice of including the area code of a telephone number when dialing to initiate a telep ...

mandatory in the area, with eleven-digit dialing necessary from landlines.

Service area

City and County of San Francisco

Marin County

* Bel Marin Keys *

Belvedere Belvedere (from Italian, meaning "beautiful sight") may refer to: Places Australia *Belvedere, Queensland, a locality in the Cassowary Coast Region Africa * Belvedere (Casablanca), a neighborhood in Casablanca, Morocco *Belvedere, Harare, Zi ...

* Black Point-Green Point *

Bolinas Bolinas is an unincorporated coastal community and census-designated place in Marin County, California, United States. As of the 2020 census it had a population of 1,483. It is located on the California coast, approximately (straight line dist ...

* California Park * Corte Madera *

Dogtown Dogtown or Dog Town may refer to: Entertainment * ''Dogtown'' (film), a 1997 film * "Dogtown" (''The Simpsons''), a 2017 season episode * '' DogTown'', a National Geographic Channel series * ''Dogtown'', a 2006 television show, starring Geraldine ...

* Fairfax *

Greenbrae Greenbrae is a small unincorporated community in Marin County, California. It is located south-southeast of downtown San Rafael, at an elevation of 33 feet (10 m), located adjacent to U.S. Route 101 at the opening of the Ross Valley. Part of ...

* Inverness Park *

Inverness Inverness (; from the gd, Inbhir Nis , meaning "Mouth of the River Ness"; sco, Innerness) is a city in the Scottish Highlands. It is the administrative centre for The Highland Council and is regarded as the capital of the Highlands. Histori ...

Kentfield Kentfield (formerly Ross Landing, Tamalpais, and Kent) is a census-designated place (CDP) in Marin County, California, United States, just north of San Francisco. Kentfield is located southwest of downtown San Rafael, at an elevation of 115 fee ...

Lagunitas-Forest Knolls Lagunitas-Forest Knolls is a census-designated place, composed of two unincorporated areas in the western half of the San Geronimo Valley in Marin County, California. It is located to the west of San Geronimo and Woodacre. The population was 1,9 ...

* Larkspur * Lucas Valley-Marinwood * Manor * Marconi *

Marin City Marin City is an unincorporated community and census-designated place (CDP) in Marin County, California, United States. As of the 2020 census, it had a population of 2,993, up from 2,666 in 2010. It is located northwest of downtown Sausalito, ...

Marshall Marshall may refer to: Places Australia * Marshall, Victoria, a suburb of Geelong, Victoria Canada * Marshall, Saskatchewan * The Marshall, a mountain in British Columbia Liberia * Marshall, Liberia Marshall Islands * Marshall Islands, an i ...

* McNears Beach *

Mill Valley Mill Valley is a city in Marin County, California, United States, located about north of San Francisco via the Golden Gate Bridge and from Napa Valley. The population was 14,231 at the 2020 census. Mill Valley is located on the western and ...

Muir Beach Muir Beach is a census designated place (CDP), unincorporated community, and beach on the Pacific Ocean. The community is located northwest of San Francisco in western Marin County, California, Marin County, California, United States. Unlike many ...

Nicasio Nicasio ( ; Spanish for " Nicasius") is an unincorporated community and census-designated place in Marin County, California, United States. It is located west-southwest of Novato, at an elevation of . As of the 2020 census the CDP population w ...

Novato Novato ( Spanish for "Novatus") is a city in Marin County, California, in the North Bay region of the Bay Area. At the 2020 census, Novato had a population of 53,225. History What is now Novato was originally the site of several Coast Miwok ...

* Olema * Paradise Cay *

Point Reyes Station Point Reyes Station (formerly, Marin and Olema Station) is a small unincorporated town in western Marin County, California, United States. Point Reyes Station is located south-southeast of Tomales, at an elevation of . Point Reyes Station is loc ...

Ross Ross or ROSS may refer to: People * Clan Ross, a Highland Scottish clan * Ross (name), including a list of people with the surname or given name Ross, as well as the meaning * Earl of Ross, a peerage of Scotland Places * RoSS, the Republic of Sou ...

* San Anselmo * San Geronimo *

San Quentin San Quentin State Prison (SQ) is a California Department of Corrections and Rehabilitation state prison for men, located north of San Francisco in the unincorporated place of San Quentin in Marin County. Opened in July 1852, San Quentin is the ...

* San Rafael *

Santa Venetia Santa Venetia is a census-designated place (CDP) in Marin County, California, United States. It is located north of downtown San Rafael, at an elevation of . The population was 4,289 at the 2020 census. Geography Santa Venetia is located in eas ...

Sausalito Sausalito (Spanish for "small willow grove") is a city in Marin County, California, United States, located southeast of Marin City, south-southeast of San Rafael, and about north of San Francisco from the Golden Gate Bridge. Sausalito's ...

* Sleepy Hollow * Stinson Beach *

Strawberry The garden strawberry (or simply strawberry; ''Fragaria × ananassa'') is a widely grown hybrid species of the genus '' Fragaria'', collectively known as the strawberries, which are cultivated worldwide for their fruit. The fruit is widely ap ...

Tamalpais-Homestead Valley Tamalpais-Homestead Valley is a census-designated place (CDP) in Marin County, California, United States. The population was 11,492 at the 2020 census. Geography Tamalpais-Homestead Valley is located at . It is bordered by Mill Valley to the nort ...

* Tiburon * Woodacre

San Mateo County

References

External links

List of exchanges from AreaCodeDownload.com, 415 Area Code
{{coord, 38, -122.6, region:US-CA_type:adm2nd, display=title 415 Culture of San Francisco 415 Marin County, California Northern California Telecommunications-related introductions in 1947