415 area code — San Francisco and Marin County, CA
The original Bay Area code, one of California’s first three in 1947, and the one that could not be split: by 2013 about two-thirds of its numbers were in a single San Francisco exchange, so the city got an overlay, 628, instead of a new map.
New numbers available in 415Area code 415 covers the City and County of San Francisco, most of Marin County — San Rafael, Novato, Mill Valley, Sausalito, Tiburon and the towns between — and a corner of San Mateo County at Brisbane and part of Daly City.
It is one of the original codes of 1947 and once covered central California from 916 in the north to 213 in the south. Since March 21, 2015 it has shared its whole area with 628: a new San Francisco line can carry either code, and every call is dialled with 1 plus ten digits.
Area code 415 at a glance
- State
- California
- County
- San Francisco, most of Marin, and a corner of San Mateo
- Region
- San Francisco and Marin County
- Time zone
- Pacific Time (PT)
- In service since
- 1947
- Type
- Geographic code
How a 415 number is built
Every North American number has four parts. Knowing where the seams fall answers most of what people ask about 415.
The code and the exchange together are the NPA-NXX: what each group of digits means.
Cities and areas served by 415
- San Francisco
- San Rafael
- Novato
- Mill Valley
- Sausalito
- Tiburon
- Brisbane
Codes sharing the same area
One other code covers the same ground as 415.
Nearby area codes
Bordering California and the surrounding region. A number in one of these is close to 415 but not in it.
How 415 came about
One of California’s first three codes, trimmed four times, then overlaid when it could no longer be split.
- 1947One of California’s first three codesThe first national numbering plan gives California three codes. 415 takes central California, south of 916 and north of 213, with San Francisco at its heart.
- 1950The map is redrawnCalifornia’s boundaries are realigned. 916 shrinks to the north-eastern corner of the state and 415 is stretched along the north coast all the way to the Oregon border.
- March 1, 1959A three-way split707 is created for the northern coast, excluding Marin County, and 408 for the South Bay. 415 keeps San Francisco, the East Bay, the Peninsula and Marin.
- September 2, 1991The East Bay becomes 510Oakland and the East Bay move to a new code across the bay. 415 is left with San Francisco, San Mateo County and Marin.
- August 2, 1997The Peninsula becomes 650The line roughly follows the border between San Francisco and San Mateo County. San Francisco and Marin keep 415; San Mateo County gets 650, apart from Brisbane and part of Daly City, which stay with the city.
- 1998–1999An overlay is approved, then shelvedWith new telephone companies entering the market, NANPA petitions the CPUC for a new code in December 1998. On April 1, 1999 the commission approves 628 as an overlay, then on December 16, 1999 suspends every overlay it had approved. Thousand-block number pooling and other conservation measures keep 415 going for another fifteen years.
- December 19, 2013The overlay returnsWith 415 forecast to run out of prefixes in the third quarter of 2015, the CPUC approves the 628 overlay in Decision 13-12-055. Of 954 public comments, 834 supported an overlay and 99 a split.
- February 21 and March 21, 2015Ten digits, then 628Dialling 1 plus the area code becomes mandatory for every call on February 21, 2015. The first 628 numbers can be issued from March 21. No 415 number changes.
Which code should you choose?
Two codes cover San Francisco and Marin identically. The codes around the bay are different places.
| Code | Covers | How it reads |
|---|---|---|
| 415 | San Francisco and Marin since 1947 | The original; 786 of its 792 possible prefixes are assigned |
| 628 | The same area since March 21, 2015 | Just as local, and where most of the spare prefixes are |
| 650 | San Mateo County and the Peninsula | South of the city line since 1997 |
| 510 and 341 | Oakland and the East Bay | Across the bay; not San Francisco |
| 408 and 669 | San Jose and the South Bay | The far end of the bay; not San Francisco |
| 707 | The North Coast beyond Marin | Marin stayed in 415 when 707 was created |
Callers read 415 and 628 as the same San Francisco number. 415 is the one people recognise, but a 628 number is just as much a San Francisco number, and 628 is where the room for new numbers is.
415 by the numbers
Counted from prefix assignment records on October 19, 2026. A prefix is the middle three digits of a number, and each one holds up to 10,000 lines. The three San Francisco rate centres are shown as one row.
| Rate centre | 415 | 628 |
|---|---|---|
| San Francisco | 601 | 116 |
| San Rafael | 62 | 17 |
| Novato and Ignacio | 34 | 13 |
| Sausalito | 18 | 7 |
| Mill Valley | 16 | 7 |
| Belvedere | 15 | 10 |
| Corte Madera | 13 | 7 |
| West Marin: Point Reyes, Stinson Beach–Bolinas, Nicasio, Inverness | 27 | 16 |
| Total prefixes | 786 | 193 |
415 has 786 of its 792 possible prefixes assigned, which is why the CPUC had to act in 2013 and why most of the room for new numbers is now in 628. Three quarters of 415’s prefixes sit in San Francisco itself; in 2013 the commission found about 65% of the code’s numbers in one rate centre, San Francisco Central, which ruled out a split.
What people get wrong about 415
Is 415 used for spam calls?
A 415 number reads as San Francisco, which is exactly why it is worth spoofing: it looks local to millions of people and gets answered. Caller ID is a field the calling system fills in, not evidence of where a call began, and a 415 or 628 number on the screen says nothing about whether the caller is in the city. Carriers attach STIR/SHAKEN attestation to calls, which catches a good deal of spoofing, but the test is the request, not the digits: a call that asks for payment, a one-time code or account details should be ended and the organisation called back on a number you already hold.
Sources
- NANPA area code report: 415 (npa_report.csv, file dated October 19, 2026: 415 in service 1947; overlay complex 415/628; 628 assigned 19-Dec-2013 and in service 21-Mar-2015; 408 in service 1959, 510 02-Sep-1991 and 650 02-Aug-1997, each with parent 415; 341 in service 22-Jul-2019 over 510; 1+10-digit local dialling)
- CPUC press release, December 19, 2013: CPUC approves new 628 area code overlay to 415 area code (exhaust expected by October 2015; 1947 origin between 916 and 213 and the 1950 realignment; the March 1, 1959 three-way split, 510 on September 2, 1991 and 650 on August 2, 1997; the December 1998 petition and the conservation measures that followed)
- CPUC Decision 13-12-055, Application 13-05-013 (14 rate centres, three in San Francisco and eleven in Marin; about 65% of numbers in San Francisco Central; projected lives of 23 and 67 years under a split; the April 1, 1999 approval in D.99-04-025 and the December 16, 1999 suspension in D.99-12-051; exhaust in the third quarter of 2015; 954 comments, 834 for an overlay and 99 for a split)
- CPUC release, January 22, 2015: San Francisco and parts of Marin County to dial calls differently (mandatory 1 + area code + number from February 21, 2015; 628 numbers issued from March 21, 2015; the communities served; local calls and prices unchanged; 911 unaffected)
- CPUC report on the 415 area code, November 28, 2000 (overlay approved April 1, 1999 and scheduled for October 21, 2000; suspended in response to public opposition to new area codes)
- NANPA 2026-1 NPA exhaust projections, April 2026 (415/628 projected to exhaust in 4Q 2072, from 1Q 2065 in the October 2025 forecast)
- Prefix assignment records for 415 and 628 (read October 19, 2026: 786 prefixes assigned in 415 and 193 in 628, across fourteen rate centres)
- Area codes 415 and 628 (Brisbane and part of Daly City as the San Mateo County portion; one of the original 1947 codes)
Area code 415 FAQ
Where is area code 415?
Area code 415 is San Francisco, California, and most of Marin County to the north: San Rafael, Novato, Mill Valley, Sausalito, Tiburon and the towns of West Marin. It also reaches a corner of San Mateo County at Brisbane and part of Daly City.
Is 415 a San Francisco area code?
Yes. 415 has been San Francisco’s code since 1947. Since March 21, 2015 it has shared the whole area with 628, so a San Francisco number can begin with either.
What is the difference between 415 and 628?
Nothing geographic. 628 is an overlay added on March 21, 2015 that covers exactly the same area. 415 is the original and is nearly full, with 786 of its 792 possible prefixes assigned; 628 holds most of the room for new numbers.
What cities are in the 415 area code?
San Francisco; in Marin County, San Rafael, Novato, Mill Valley, Sausalito, Tiburon, Belvedere, Corte Madera, Larkspur, San Anselmo, Fairfax, Ross, Stinson Beach, Point Reyes and Inverness; and in San Mateo County, Brisbane and part of Daly City.
What time zone is the 415 area code in?
Pacific Time: UTC−8 in winter and UTC−7 during daylight saving time.
When did the 415 area code start?
In 1947, with the first North American numbering plan, as one of California’s first three codes. It then covered central California from 916 in the north to 213 in the south.
Do I need to dial 1 and the area code for local calls in San Francisco?
Yes. Since February 21, 2015 every call from a 415 or 628 phone is dialled as 1 + area code + number, including local calls. Three-digit numbers such as 911 still work.
Is 415 running out of numbers?
The code itself is nearly full: 786 of its 792 possible prefixes are assigned. But 415 and 628 are managed as one pool, and NANPA’s April 2026 forecast does not expect the pair to run out until the fourth quarter of 2072.
Is Oakland in the 415 area code?
Not since September 2, 1991, when the East Bay became 510. Oakland now uses 510 and its 2019 overlay, 341.
Why did San Francisco get an overlay instead of a split?
Because 415 could not be divided fairly. In 2013 about 65% of its numbers were in one rate centre, San Francisco Central, so any split would have given one side 23 years of numbers and the other 67. The CPUC chose an overlay in Decision 13-12-055, and 834 of 954 public comments agreed.
Getting a 415 business number
415 numbers are still being issued, so a business anywhere can hold one and route it to wherever its team actually works — you do not need an address in California.
- STIR/SHAKENAttested, so calls are less likely to show as spam
- AI receptionistCover for the hours nobody is at a desk
- Free portingIf you already hold a 415 number
- Recording & SMSOn the same line, no add-on