Area codes 408 and 669
area code complex for the South Bay in California
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, Morgan Hill, Saratoga, Los Gatos, Monte Sereno, Milpitas, Sunnyvale, Santa Clara, Cupertino, Campbell, and San Jose.
Area code 408 was split from area code 415 in 1959. The numbering plan area was reduced in geographic extent in 1998 for the creation of area code 831. In 2012, area code 669 was assigned as a second area code for same numbering plan area by overlay.
History
In 1947, the American Telephone and Telegraph Company (AT&T) devised the first nationwide telephone numbering plan and assigned the original North American area codes. The state of California was divided into three numbering plan areas (NPAs) with distinct area codes: 213, 415, and 916, for the southern, central, and northern parts of the state, respectively. California area codes were reorganized geographically in 1950, so that 916 was assigned to a numbering plan area that comprised only the northeastern part from the Sierra Nevada to the Central Valley. The coastal area to the west was assigned area code 415.
Area code 408 was split from numbering plan area 415 in a flash-cut (without permissive dialing period) on March 1, 1959.
Begin with the source’s own compact description: “Area codes 408 and 669” is area code complex for the South Bay in California. The dossier treats that line as a proposition to test through Area, codes and area, not as a finished interpretation.
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Vocabulary and entity names are the principal evidence signals here, because they determine the precision of every later search. The source revision retrieved here is dated May 29, 2026. The linked authority identifier is Q3150337. Authority coordinates are 37.256, -121.983. 1 of 2 selected statements include explicit references; 0 carry qualifiers and 0 use preferred rank. The first chronological checks are 1959, 1998, 2012 and 1947.
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This entry incorporates text from “Area codes 408 and 669” on English Wikipedia. Contributors are listed in the page history. Text is available under the Creative Commons Attribution-ShareAlike 4.0 License. Selected authority identifiers and statements are retrieved from Wikidata under CC0; their references and qualifiers remain part of the verification path.