North American Numbers Source-cited · ownership disclosed
Area code
415
In service
United States · since 1947

San Francisco

Area code 415 is one of the original 1947 North American area codes, now serving San Francisco, Marin County, and a small northeastern part of San Mateo County. It is overlaid by area code 628.

The essentials Numbering data · NumberResearch · as of 2026-09-18
Place
San Francisco
Type
geographic
Status
in service
In service since
1947
Projected exhaust
2072 Q4

Status, dates and counts are read from NumberResearch (NANPA / CNAC / FCC records). Assignment records show initial assignees, not the carrier serving a number today.

A · Where it is

Where 415 is

City and County of San Francisco, Marin County, and northeastern San Mateo County (Brisbane, Daly City)..

Communities served wholly or partly by 415:

San FranciscoSan RafaelNovatoMill ValleySausalitoDaly City

Representative list; Marin County includes many additional communities.

B · Relationships

How it relates to other codes

The codes 415 was split from, spawned, or shares its area with. A split divides the map and changes some numbers; an overlay shares the same ground and changes none — what's the difference?

Overlay · 2015 628 San Francisco (overlay) All-services overlay of the 415 area, in service February 21, 2015.
Spawned · 1959 408 San Jose San Jose/South Bay split off from 415 in 1959.
Spawned · 1959 707 Santa Rosa / North Bay North Bay/North Coast split off from 415 in 1959 (per Wikipedia; some sources cite 916 — see uncertainty).
Spawned · 1991 510 Oakland East Bay split off from 415 on September 2, 1991.
Spawned · 1997 650 San Mateo / Palo Alto San Mateo Peninsula split off from 415 on August 2, 1997.
What's changing. Overlaid by 628; mandatory ten-digit dialing.
C · History

How 415 got here

1947
Area code 415 established as one of the original NANP area codes.
Source: Wikipedia
1959
707 (north) and 408 (San Jose/South Bay) split from 415.
Source: Wikipedia
1991-09-02
Area code 510 created from 415 for the East Bay.
Source: Wikipedia
1997-08-02
Area code 650 split from 415 for San Mateo County.
Source: Wikipedia
2015-02-21
Overlay 628 added; mandatory ten-digit dialing began.
Source: Wikipedia
D · Capacity

How full it is

Prefixes assigned
800
Prefixes available
0
Thousands-blocks assigned
2,894

Prefix-assignment counts describe allocation to carriers, not how many individual numbers are in use. Full technical records: NumberResearch ↗.

Compare 415 with another code →
Sources
Wikipedia ↗
Area codes 415 and 628
NumberResearch.org ↗
Live status, dates, assignment counts and exhaust forecast — data as of 2026-09-18 (CC BY 4.0).

Place, relationships and history above are compiled by North American Numbers from the sources listed and last checked 2026-09-18. A check date is not an expert review — see how this is made. Flag an error.