Area code 415 is one of the first three area codes in California, created in 1947. Its territory has shrunk through several splits. Today it covers San Francisco, most of Marin County, and a small portion of San Mateo County, and area code 628 shares the same territory as an overlay.
Quick answer
- 415 was created in 1947 as one of the first three area codes in California, covering the north coastal area of the state. It now serves San Francisco and most of Marin County.
- It covers San Francisco, most of Marin County, and a small portion of San Mateo County, including Brisbane and Daly City.
- Area code 628 was added to the same territory as an overlay, effective March 21, 2015.
- Calls placed from 415 or 628 numbers are dialed as 1, the area code, and the seven-digit number.
The essentials
415 area code: quick facts
| Area code | 415 |
| Coverage | San Francisco, most of Marin County, and a small portion of San Mateo County, including Brisbane and Daly City |
| State | California |
| Time zone | Pacific Time (PT) |
| Assigned | 1947, one of the first three area codes in California |
| Overlay on the same territory | 628 (overlay effective March 21, 2015) |
Pacific Time is the zone in the IANA time zone database as America/Los_Angeles. Under that database's U.S. rule, clocks move forward at 2:00 a.m. on the second Sunday in March and back at 2:00 a.m. on the first Sunday in November.
How 415 became San Francisco's code
- 1947: 415 is created with the nationwide area code plan. It is one of the first three area codes in California and covers the entire north coastal area of the state.
- 1959: 707 and 408 split off from 415.
- 1991: 510 splits off from 415.
- 1997: 650 splits off from 415.
- December 2013: CPUC Decision 13-12-055 grants an overlay of 628 on the 415 region. The decision is dated December 19, 2013.
- March 21, 2015: The overlay takes effect, according to the CPUC 415/628 page. Existing 415 numbers keep their code.
Where area code 415 is used
415 covers the City and County of San Francisco and most of Marin County. The CPUC 415/628 page lists Marin cities served by 415 and 628, including Mill Valley, Novato, Sausalito, San Rafael, and Tiburon.
The CPUC 415/628 page says the two codes serve a small portion of San Mateo County and lists Brisbane and Daly City among the cities served. An area code shows only the general territory, so confirm the location of a specific number with your provider.
Splits that reduced 415
Four area codes were split off 415 between 1959 and 1997. The CPUC decision and the CPUC 415/628 page list no split since 1997. The 2015 change was an overlay, which added 628 without taking territory.
| Code | Year | Result |
|---|---|---|
| 707 | 1959 | Split off from 415 |
| 408 | 1959 | Split off from 415 |
| 510 | 1991 | Split off from 415 |
| 650 | 1997 | Split off from 415 |
Neighboring area codes around San Francisco
The table shows how each nearby code relates to 415. The codes that split from 415 are no longer part of its territory.
| Code | Where it applies | Relation to 415 |
|---|---|---|
| 415 | San Francisco, most of Marin County, and a small portion of San Mateo County | Original code for the territory (1947) |
| 628 | The same territory as 415 | Overlay added in 2015 |
| 510 | Not part of 415 territory | Split from 415 in 1991 |
| 650 | Not part of 415 territory | Split from 415 in 1997 |
| 707 | Not part of 415 territory | Split from 415 in 1959 |
| 408 | Not part of 415 territory | Split from 415 in 1959 |
Overlay code 628: the same territory as 415
An overlay adds a new area code to a territory that already has one. The CPUC says the 628 overlay was approved to accommodate the need for additional telephone numbers in the 415 area code region. In the same decision, NANPA projected that the 415 code would exhaust in the third quarter of 2015. The CPUC also says existing 415 customers keep their numbers and the 415 code.
- 415 (1947): the original code for San Francisco and most of Marin County.
- 628 (2015): overlaid on the same territory, so both codes are used in the same places.
Because the two codes overlap, neighbors on the same block can have different area codes. A 415 or 628 number does not show which building or floor it belongs to.
| Code | Added | Where it applies |
|---|---|---|
| 415 | 1947 | San Francisco, most of Marin County, and a small portion of San Mateo County |
| 628 | 2015 | The same territory as 415 |
How to dial a 415 number
The CPUC says calls placed from 415 or 628 numbers are dialed as 1, the area code, and the seven-digit number. Dialing the 1 does not make a call a toll or long distance call, and calls to 911 and the other three-digit codes are not affected. The 2013 decision describes the overlay rule as 1+10 digit dialing for customers with a 415 area code. The CPUC gives March 21, 2015 as the overlay's effective date.
Caller ID, spoofing, and 415 scams
The FTC's phone scams guidance says scammers can make any name or number show up on caller ID, and calls like this are called spoofing. A local-looking number is therefore not proof that a caller is nearby.
- The FTC's phone scams page advises hanging up on scam calls. A call that looks local can still be a scam.
- Do not press numbers to speak with a live operator or to be removed from a robocall list, the FTC advises.
- Report the number a caller told you to call back to the FTC.
Using a 415 number for business
Because 415 and 628 serve the same territory, a 415 number and a 628 number both point to San Francisco or most of Marin County. Neither code tells a caller which team, office, or floor they reached, so routing has to be set by rule, not by area code.
Neighboring codes cover other territory. 510, 650, 408, and 707 were split off from 415, so they are not part of its territory. If your business serves those areas, set routing for them separately. An area code shows where a number was assigned, not where your team sits, and whether a specific 415 or 628 number is available depends on your provider and its inventory when you ask.
Important: Confirm availability with your provider before you plan a campaign or print a number on materials.
Before you use a 415 number
- Confirm the number is available from your provider, and get its terms in writing.
- Ask who owns the number and whether it can be moved to another provider if you switch.
- Make sure your phone system routes calls from both 415 and 628 to the right team, since both codes cover the same territory.
- Set 1, area code, and seven-digit dialing for calls placed from 415 and 628 numbers before you go live, and test a call in that format.
- Check how your system handles 510, 650, 408, and 707 numbers separately, because those codes are outside 415 territory.
- If you already hold a 415 number, confirm with your provider that it keeps the 415 code. The CPUC says existing 415 customers keep their numbers.
- Plan for caller ID. A local number does not prove who is calling, and caller ID can be spoofed.
Frequently asked questions
Which area is the 415 area code for?
Area code 415 serves the City and County of San Francisco and most of Marin County. The CPUC page also says 415 and 628 serve a small portion of San Mateo County, and lists Brisbane and Daly City among the cities served.
Is area code 415 being split or replaced?
The CPUC 415/628 page describes the 2015 overlay, in which area code 628 was added to the same territory, and does not mention a planned split or replacement. Check NANPA for current status.
Is 628 a different place from 415?
No. Area code 628 covers the same territory as 415. It was added as an overlay, so both codes serve San Francisco and most of Marin County.
Do I need to dial 1 before a 415 number?
Yes, for calls placed from 415 or 628 numbers. The CPUC says they need to be dialed as 1, the area code, and the seven-digit number, 11 digits in all. Without the 1 and the area code, the call will not be completed, although some cell phone callers on certain providers may be able to complete calls without the 1.
Does a 415 number have to change because of 628?
No. The CPUC says the overlay allows all existing 415 customers to keep their telephone numbers and the 415 area code.
Does a 415 number prove the caller is in San Francisco?
No. Scammers can make any name or number show up on caller ID, a practice called spoofing. The FTC warns that a local-looking number can be a scammer calling from anywhere in the world.
Sources · reviewed October 2026
Decision 13-12-055, California Public Utilities Commission
Used for the 1947 creation and its place among the first three California codes, the 1959, 1991, and 1997 splits, the December 19, 2013 decision date, the 1+10 digit dialing note, and the NANPA exhaustion projection. The CPUC web page gives December 14, 2014 for the same approval; this page follows the decision's own date.
415/628 Area Code, California Public Utilities Commission
Used for the March 21, 2015 effective date of the 628 overlay, the coverage statement (greater San Francisco Bay area, the majority of Marin County, a small portion of San Mateo County, and the cities listed), the rule that existing 415 customers keep their numbers, the 1 + area code + 7-digit dialing rule, and the rule that 911 and other three-digit codes are unchanged.
Phone Scams, Federal Trade Commission
Used for the spoofing definition, the statement that a local-looking number can come from a scammer anywhere in the world, and the advice on robocall keypresses and call-back numbers. The FCC caller ID spoofing guide gives the same definition.
tz database, North America data (IANA)
Used for the America/Los_Angeles zone (Pacific Time) and the U.S. daylight saving rule: second Sunday in March to first Sunday in November, switching at 2:00 local time.