Area code
661
661 is a United States area code. Under the North American Numbering Plan it belongs to California, which has 41 area codes in total.
Validate a number in 661
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Area code 661 at a glance
NANPA lists 668 central office codes (prefixes) in use in area code 661, held by 50 holders across 32 rate centers.
| Fact | Value |
|---|---|
| In service since | 1999-02-13 |
| Time zone | Pacific (P) |
| Prefixes in use | 668 |
| Pooled prefixes | 525 (79%) |
| Rate centers | 32 |
| Companies holding prefixes | 50 |
| Assignment dates on file | 2001-02-07 to 2026-03-30 (258 prefixes) |
| ZIP codes in its places | 26 |
Rate centers in area code 661
| Rate center | Prefixes | Share |
|---|---|---|
| BKFD MAIN | 149 | 22% |
| PLDL PLDL | 95 | 14% |
| SNCA NHCS | 66 | 10% |
| LANCASTER | 55 | 8% |
| BKFD SOUTH | 49 | 7% |
| BKFD NORTH | 29 | 4% |
| SNCA SGCC | 29 | 4% |
| DELANO | 23 | 3% |
| 24 other rate centers | 173 | 26% |
Who holds the prefixes in 661
Pacific Bell holds the most prefixes, 144 (22%). 79% of the prefixes are pooled, which means their thousands-blocks can belong to different companies.
| Holder | Prefixes | Share |
|---|---|---|
| Pacific Bell | 144 | 22% |
| New Cingular Wireless PCS | 75 | 11% |
| T-Mobile USA | 55 | 8% |
| Verizon Wireless | 49 | 7% |
| Onvoy | 47 | 7% |
| Level 3 Communications | 35 | 5% |
| 44 other carriers | 263 | 39% |
A prefix holder is the company a code was assigned to, not necessarily a number's current carrier, because numbers can be ported to another company. Find which carrier a number is on, or browse the prefix holders.
History of area code 661
- 1957-01-01 Area code 805, named as the parent of 661 in the NANPA report, was in service.
- 1999-02-13 Area code 661 went into service.
Area codes nearest to 661
Distance is measured between the centers of the ZIP code places each area code serves, so it is a rough guide.
ZIP codes in area code 661
26 ZIP codes fall in places that have a rate center in this area code.
| Place | ZIP codes |
|---|---|
| Lancaster, CA | 6 |
| Delano, CA | 2 |
| Edwards, CA | 2 |
A ZIP code and an area code are unrelated systems. A ZIP code can sit in more than one area code, and an area code spans many ZIP codes.
Complaints on file for 661 numbers
3,100 FCC complaints are on file for 2,281 numbers in 661, most often filed as "Unwanted Calls". These are unverified consumer reports.
| Year of latest complaint | Numbers |
|---|---|
| 2023 | 113 |
| 2024 | 134 |
| 2025 | 92 |
Other area codes in California
California is one state with 41 area codes in the NANPA table. 661 is one of them.
- 209
- 213
- 279
- 310
- 323
- 341
- 350
- 357
- 369
- 408
- 415
- 424
- 442
- 510
- 530
- 559
- 562
- 619
- 626
- 628
- 650
- 657
- 669
- 707
- 714
- 738
- 747
- 760
- 805
- 818
- 820
- 831
- 837
- 840
- 858
- 909
- 916
- 925
- 949
- 951
Next to 661 in the numbering table
These are the codes just before and after 661 when all are sorted by number. They are neighbours on the list, not necessarily on the map.
What the area code does and does not tell you
A number that starts with 661 was first assigned in California. That is a fact about where the number began, and it is a useful hint when you check a form entry, for example a billing address in California next to a 661 phone number.
It does not show where the person is today. A number stays with its owner after a move or a change of provider (number portability), and mobile numbers travel with the handset. The area code also cannot tell you whether the line is active, who the carrier is, or whether the number is mobile or fixed: the plan shares those ranges. Read more about the area code, the numbering plan and line type.
Check numbers in bulk with the API
| Product | Credits | Docs |
|---|---|---|
| Phone Numbering-Plan Validation | 1 credit per valid number | API docs |
| Phone Intelligence (carrier and line status) | 1 credit per check (invalid numbers outside the US and Canada are free) | Product page |
Questions about area code 661
Where is area code 661?
NANPA assigns area code 661 to California, United States.
In which state does area code 661 sit?
California. 661 is one of 41 area codes the NANPA table assigns to the state.
Which places does area code 661 cover?
The places with the most ZIP codes among the rate centers in 661 are Lancaster, CA, Delano, CA and Edwards, CA. The rate center list on this page shows all of them.
Who owns area code 661?
NANPA assigns area codes. Within 661, Pacific Bell holds the most prefixes, 144 prefixes or 22%.
Which time zone does 661 use?
The NANPA NPA report lists the time zone for 661 as Pacific (P).
What year did 661 enter service?
The NANPA NPA report gives an in-service date of 1999-02-13, so 661 has been in use since 1999.
Does area code 661 have an overlay?
The NANPA NPA report lists no other area code in an overlay with 661.
Which area codes are nearest to 661?
The area codes closest to 661, measured between the centers of the ZIP code places they serve, are 747 (about 69 miles), 805 (about 69 miles), 818 (about 69 miles), 820 (about 70 miles) and 626 (about 83 miles).
How many prefixes does area code 661 have?
NANPA's report dated 2026-10-17 lists 668 prefixes in service in 661, spread over 32 rate centers and 50 holders.
Are there complaints about 661 numbers?
The FCC data on file has 3,100 complaints for 2,281 numbers in 661. They are unverified consumer reports. A number with no complaints on file is not proven safe.
Area code assignments: North American Numbering Plan Administrator NPA report, file dated 10/17/2026, retrieved 2026-10-17. Source file. New codes are assigned several times a year. Prefixes, rate centers, holders, time zone, in-service date and overlays: NANPA central office code report dated 2026-10-17 and NPA report dated 2026-10-18. Complaints: FCC consumer complaints open data, fetched 2026-10-17. ZIP code places: Postal code places and coordinates: GeoNames (geonames.org), licensed CC BY 4.0.