View source for Area codes 415 and 628

{{short description|Area codes for San Francisco and Marin County, California}}
{{California area codes image map|415 and 628}}
'''Area codes 415 and 628''' are [[telephone]] [[area code]]s in the [[North American Numbering Plan]] (NANP) for the city of [[San Francisco]] and its northern suburbs in [[Marin County, California|Marin County]] (across the [[Golden Gate]]), and the northeast corner of [[San Mateo County, California|San Mateo County]] in the U.S. state of [[California]]. Area code 415 was one of the eighty-six [[original North American area codes]] established in 1947, but modified in geographic configuration later. Area code 628 was assigned in 2015 to form an [[overlay plan|overlay]] in that numbering plan area in mitigation of central office prefix exhaustion.

==History==
When the [[American Telephone and Telegraph Company]] (AT&T) introduced the first nationwide [[telephone numbering plan]] for [[Operator Toll Dialing]] in 1947, the state of [[California]] was divided into three geographical numbering plan areas (NPAs).<ref>{{cite journal |last=Mabbs |first=Ralph I. |title=Nation-wide Operator Toll Dialing—the Coming Way |journal=Bell Telephone Magazine |date=Winter 1947–1948 |volume=26 |issue=4 |page=181 |url=https://archive.org/details/sim_bell-telephone-magazine_winter-1947-1948_26_4/page/n5/ |access-date=2022-12-26}}</ref> Area code 415 was assigned to central California, with [[area code 916]] assigned to the northern part  [[area code 213]] assigned to the southern part. Originally, 415 stretched from [[Sacramento]] in the north to [[Bakersfield, California|Bakersfield]] in the south.<ref>{{cite web |last=Madison|first=Linc|url=http://www.lincmad.com/map1947.html |title=LincMad's 1947 Area Code Map|date=1999-05-27 |access-date=2007-01-06| archive-url= https://web.archive.org/web/20070104181058/http://www.lincmad.com/map1947.html| archive-date= 4 January 2007 | url-status= live}}</ref>

In 1950, the boundaries of the numbering plan areas of California were redrawn to produce a division of the northern and central parts along a north–south dividing line. 415 was designated to the coastal region from the [[North Coast (California)|North Coast]] to the [[Oregon]] border, while 916 comprised the northeastern corner of the state.<ref>{{cite journal|last=Moore|first=Carl|journal=TELECOM Digest|url=http://massis.lcs.mit.edu/archives/areacodes/history.area.splits.2-96 |title=history.of.area.splits|date=1996-02-12 |access-date=2007-01-06|archive-url=https://archive.today/20120710002143/http://massis.lcs.mit.edu/archives/areacodes/history.area.splits.2-96|archive-date=10 July 2012}}</ref>  As a result of this realignment, Sacramento was reassigned from 415 to 916, and Bakersfield to 213.

With the preparations for nation-wide [[direct distance dialing]] (DDD) in the early 1950s, [[area code 318]] was temporarily used in the San Francisco area, initially by customers in [[Englewood, New Jersey]], participating in the first customer trials to reach the city, as well as some areas north of the [[Golden Gate]].<ref>{{cite journal|last=Cuccia |first=Mark|journal=TELECOM Digest|url=http://www.textfiles.com/digest/TELECOMDIGEST/vol16.iss0401-0450.txt |title=Re: When Was Direct Distance Dialing Cut In?|date=1996-08-13 |access-date=2007-01-06}}</ref> In 1953, the entire Bay Area was enumerated again with area code 415.

Numbering plan area 415 has been split several times due to population growth and infrastructure changes.

In a three-way split in 1959, [[area code 707]] was created from the northern part, and [[area code 408]] was created for [[San Jose, California|San Jose]], the [[Santa Clara Valley|South Bay]], the [[Monterey Bay]], and the [[Salinas Valley]].<ref>{{cite web|last=Madison |first=Linc |url=http://www.areacode-info.com/!history/1940s50s.htm |archive-url=https://web.archive.org/web/20020911092304/http://areacode-info.com/!history/1940s50s.htm |url-status=dead |archive-date=2002-09-11 |title=NANP Area Code History: 1948 - 1959 |access-date=2007-01-06 }}</ref>  (408 has since been split to [[Area code 831|831]] and overlaid with 669. 707 has since been overlaid with [[Area code 369|369]].)

On September 2, 1991, [[area code 510]] was created for the [[East Bay]], including [[Oakland, California|Oakland]].<ref>{{cite journal|last=Fabisch|first=M.P.|journal=Bellcore Letter|url=http://www.nanpa.com/pdf/old_pl/IL%2090-06-023.pdf|title=NANPA Revised Date for Split of 415 (California) Numbering Plan Area|date=1990-06-13|access-date=2007-01-06|archive-url=https://web.archive.org/web/20110604120756/http://www.nanpa.com/pdf/old_pl/IL%2090-06-023.pdf|archive-date=2011-06-04|url-status=dead}}</ref>  (510 has since been split to [[Area code 925|925]] and was overlaid by 341 in 2019.)

On August 2, 1997, [[area code 650]] was created for most of [[San Mateo County, California|San Mateo County]]. The partition approximately followed the boundary between San Francisco, which (along with Marin County) kept 415, and San Mateo County. Deviations from the county line included a very small area east of the [[San Francisco Golf Club]], which was changed to 650,<ref>{{cite web|url=http://www.att.com/gen/press-room?pid=4800&cdvn=news&newsarticleid=4002 |title=AT&T- News Room |publisher=Att.com |date=1998-01-28 |access-date=2012-09-07}}</ref> and portions of [[Brisbane, California|Brisbane]] and [[Daly City, California|Daly City]], which remained in 415.<ref>{{cite journal|last=Deak|first=J.N.|journal=North American Numbering Plan Letter|volume=PL-NANP-022|url=http://www.nanpa.com/pdf_previous/08_02_99/pl_nanp_022.pdf|title=NANPA Revised Date for Split of 415 (California) Numbering Plan Area|date=1996-11-22|access-date=2007-01-06|archive-date=2008-12-30|archive-url=https://web.archive.org/web/20081230155337/http://www.nanpa.com/pdf_previous/08_02_99/pl_nanp_022.pdf|url-status=dead}}</ref>

On February 21, 2015, the numbering plan area was converted to an [[overlay complex]] by adding '''area code 628''' to the same service area,<ref>{{Cite web |url=http://www.cpuc.ca.gov/PUC/Telco/generalInfo/Area+Codes/415+Area+Code.htm |title=415 Area Code|website=California Public Utilities Commission |access-date=2015-02-25 |archive-url=https://web.archive.org/web/20150226025654/http://www.cpuc.ca.gov/PUC/Telco/generalInfo/Area+Codes/415+Area+Code.htm |archive-date=2015-02-26 |url-status=dead }}</ref> making [[ten-digit dialing]] mandatory in the area, with prefix ''1'' from landlines.<ref>{{Cite web|url=https://www.sfgate.com/bayarea/article/Starting-Saturday-415-shares-the-city-with-6090563.php|title=415, meet 628: New S.F. area code debuts Saturday|last=Rubenstein|first=Steve|date=2015-02-20|website=SFGate|access-date=2020-04-26}}</ref>

==Service area==
===City and County of San Francisco===
*[[San Francisco]]

===Marin County===
{{div col|colwidth=9em}}
*[[Bel Marin Keys, California|Bel Marin Keys]]
*[[Belvedere, California|Belvedere]]
*[[Black Point-Green Point, California|Black Point-Green Point]]
*[[Bolinas, California|Bolinas]]
*[[California Park, California|California Park]]
*[[Corte Madera, California|Corte Madera]]
*[[Dogtown, Marin County, California|Dogtown]]
*[[Fairfax, California|Fairfax]]
*[[Greenbrae, California|Greenbrae]]
*[[Ignacio, California|Ignacio]]
*[[Inverness Park, California|Inverness Park]]
*[[Inverness, California|Inverness]]
*[[Kentfield, California|Kentfield]]
*[[Lagunitas-Forest Knolls, California|Lagunitas-Forest Knolls]]
*[[Larkspur, California|Larkspur]]
*[[Lucas Valley-Marinwood, California|Lucas Valley-Marinwood]]
*[[Manor, California|Manor]]
*[[Marconi, California|Marconi]]
*[[Marin City, California|Marin City]]
*[[Marshall, California|Marshall]]
*[[McNears Beach, California|McNears Beach]]
*[[Mill Valley, California|Mill Valley]]
*[[Muir Beach, California|Muir Beach]]
*[[Nicasio, California|Nicasio]]
*[[Novato, California|Novato]]
*[[Olema, California|Olema]]
*[[Paradise Cay, California|Paradise Cay]]
*[[Point Reyes Station, California|Point Reyes Station]]
*[[Ross, California|Ross]]
*[[San Anselmo, California|San Anselmo]]
*[[San Geronimo, California|San Geronimo]]
*[[San Quentin, California|San Quentin]]
*[[San Rafael, California|San Rafael]]
*[[Santa Venetia, California|Santa Venetia]]
*[[Sausalito, California|Sausalito]]
*[[Sleepy Hollow, Marin County, California|Sleepy Hollow]]
*[[Stinson Beach, California|Stinson Beach]]
*[[Strawberry, Marin County, California|Strawberry]]
*[[Tamalpais-Homestead Valley, California|Tamalpais-Homestead Valley]]
*[[Tiburon, California|Tiburon]]
*[[Woodacre, California|Woodacre]] 
{{div col end}}

===San Mateo County===
*[[Brisbane, California|Brisbane]]
*[[Daly City, California|Daly City]]

==See also==
*[[List of California area codes]]
*[[List of North American Numbering Plan area codes]]

==References==
{{Reflist}}

==External links==
{{Area code footer|Map=CA}}

{{Area code box|State=CA
| This=415/628
| N=[[area codes 707 and 369|707/369]]
| S=[[area code 650|650]]
| E=[[area codes 510 and 341|510/341]], [[area code 925|925]]
| W=Pacific Ocean, [[area code 808|808]]
|S1=HI}}

{{coord|38|-122.6|region:US-CA_type:adm2nd|display=title}}

[[Category:Area codes in the United States|415]]
[[Category:Culture of San Francisco]]
[[Category:Area codes in California|415]]
[[Category:Marin County, California]]
[[Category:Northern California]]
[[Category:Telecommunications-related introductions in 1947]]
[[Category:Telecommunications-related introductions in 2015]]